Documentation

Lean.Meta.Basic

This module provides four (mutually dependent) goodies that are needed for building the elaborator and tactic frameworks. 1- Weak head normal form computation with support for metavariables and transparency modes. 2- Definitionally equality checking with support for metavariables (aka unification modulo definitional equality). 3- Type inference. 4- Type class resolution.

They are packed into the MetaM monad.

Configuration flags for the MetaM monad. Many of them are used to control the isDefEq function that checks whether two terms are definitionally equal or not. Recall that when isDefEq is trying to check whether ?m@C a₁ ... aₙ and t are definitionally equal (?m@C a₁ ... aₙ =?= t), where ?m@C as a shorthand for C |- ?m : t where t is the type of ?m. We solve it using the assignment ?m := fun a₁ ... aₙ => t if

  1. a₁ ... aₙ are pairwise distinct free variables that are ​not​ let-variables.
  2. a₁ ... aₙ are not in C
  3. t only contains free variables in C and/or {a₁, ..., aₙ}
  4. For every metavariable ?m'@C' occurring in t, C' is a subprefix of C
  5. ?m does not occur in t
  • foApprox : Bool

    If foApprox is set to true, and some aᵢ is not a free variable, then we use first-order unification

      ?m a_1 ... a_i a_{i+1} ... a_{i+k} =?= f b_1 ... b_k
    

    reduces to

      ?m a_1 ... a_i =?= f
      a_{i+1}        =?= b_1
      ...
      a_{i+k}        =?= b_k
    
  • ctxApprox : Bool

    When ctxApprox is set to true, we relax condition 4, by creating an auxiliary metavariable ?n' with a smaller context than ?m'.

  • quasiPatternApprox : Bool

    When quasiPatternApprox is set to true, we ignore condition 2.

  • constApprox : Bool

    When constApprox is set to true, we solve ?m t =?= c using ?m := fun _ => c when ?m t is not a higher-order pattern and c is not an application as

  • isDefEqStuckEx : Bool

    When the following flag is set, isDefEq throws the exception Exeption.isDefEqStuck whenever it encounters a constraint ?m ... =?= t where ?m is read only. This feature is useful for type class resolution where we may want to notify the caller that the TC problem may be solvable later after it assigns ?m.

  • unificationHints : Bool

    Enable/disable the unification hints feature.

  • proofIrrelevance : Bool

    Enables proof irrelevance at isDefEq

  • assignSyntheticOpaque : Bool

    By default synthetic opaque metavariables are not assigned by isDefEq. Motivation: we want to make sure typing constraints resolved during elaboration should not "fill" holes that are supposed to be filled using tactics. However, this restriction is too restrictive for tactics such as exact t. When elaborating t, we dot not fill named holes when solving typing constraints or TC resolution. But, we ignore the restriction when we try to unify the type of t with the goal target type. We claim this is not a hack and is defensible behavior because this last unification step is not really part of the term elaboration.

  • offsetCnstrs : Bool

    Enable/Disable support for offset constraints such as ?x + 1 =?= e

  • Controls which definitions and theorems can be unfolded by isDefEq and whnf.

  • trackZetaDelta : Bool

    When trackZetaDelta = true, we track all free variables that have been zetaDelta-expanded. That is, suppose the local context contains the declaration x : t := v, and we reduce x to v, then we insert x into State.zetaDeltaFVarIds. We use trackZetaDelta to discover which let-declarations let x := v; e can be represented as (fun x => e) v. When we find these declarations we set their nonDep flag with true. To find these let-declarations in a given term s, we 1- Reset State.zetaDeltaFVarIds 2- Set trackZetaDelta := true 3- Type-check s.

  • Eta for structures configuration mode.

Instances For

    Function parameter information cache.

    • binderInfo : Lean.BinderInfo

      The binder annotation for the parameter.

    • hasFwdDeps : Bool

      hasFwdDeps is true if there is another parameter whose type depends on this one.

    • backDeps : Array Nat

      backDeps contains the backwards dependencies. That is, the (0-indexed) position of previous parameters that this one depends on.

    • isProp : Bool

      isProp is true if the parameter is always a proposition.

    • isDecInst : Bool

      isDecInst is true if the parameter's type is of the form Decidable .... This information affects the generation of congruence theorems.

    • higherOrderOutParam : Bool

      higherOrderOutParam is true if this parameter is a higher-order output parameter of local instance. Example:

      getElem :
        {cont : Type u_1} → {idx : Type u_2} → {elem : Type u_3} →
        {dom : cont → idx → Prop} → [self : GetElem cont idx elem dom] →
        (xs : cont) → (i : idx) → dom xs i → elem
      

      This flag is true for the parameter dom because it is output parameter of [self : GetElem cont idx elem dom]

    • dependsOnHigherOrderOutParam : Bool

      dependsOnHigherOrderOutParam is true if the type of this parameter depends on the higher-order output parameter of a previous local instance. Example:

      getElem :
        {cont : Type u_1} → {idx : Type u_2} → {elem : Type u_3} →
        {dom : cont → idx → Prop} → [self : GetElem cont idx elem dom] →
        (xs : cont) → (i : idx) → dom xs i → elem
      

      This flag is true for the parameter with type dom xs i since dom is an output parameter of the instance [self : GetElem cont idx elem dom]

    Instances For
      Equations
      • One or more equations did not get rendered due to their size.

      Function information cache. See ParamInfo.

      • Parameter information cache.

      • resultDeps : Array Nat

        resultDeps contains the function result type backwards dependencies. That is, the (0-indexed) position of parameters that the result type depends on.

      Instances For

        Key for the function information cache.

        • The transparency mode used to compute the FunInfo.

        • expr : Lean.Expr

          The function being cached information about. It is quite often an Expr.const.

        • nargs? : Option Nat

          nargs? = some n if the cached information was computed assuming the function has arity n. If nargs? = none, then the cache information consumed the arrow type as much as possible using the current transparency setting. X

        Instances For
          Equations
          Equations
          • One or more equations did not get rendered due to their size.

          A mapping (s, t) ↦ isDefEq s t per transparency level. TODO: consider more efficient representations (e.g., a proper set) and caching policies (e.g., imperfect cache). We should also investigate the impact on memory consumption.

          Instances For
            Equations

            Cache datastructures for type inference, type class resolution, whnf, and definitional equality.

            Instances For
              Equations
              • One or more equations did not get rendered due to their size.

              "Context" for a postponed universe constraint. lhs and rhs are the surrounding isDefEq call when the postponed constraint was created.

              Instances For

                Auxiliary structure for representing postponed universe constraints. Remark: the fields ref and rootDefEq? are used for error message generation only. Remark: we may consider improving the error message generation in the future.

                Instances For
                  Equations

                  MetaM monad state.

                  Instances For
                    Equations

                    Backtrackable state for the MetaM monad.

                    Instances For

                      Contextual information for the MetaM monad.

                      Instances For
                        Equations
                        Equations
                        Equations
                        • One or more equations did not get rendered due to their size.
                        Equations
                        • One or more equations did not get rendered due to their size.
                        Equations
                        Equations
                        Instances For

                          Restore backtrackable parts of the state.

                          Equations
                          • One or more equations did not get rendered due to their size.
                          Instances For
                            @[inline]
                            def Lean.Meta.MetaM.run {α : Type} (x : Lean.MetaM α) (ctx : optParam Lean.Meta.Context { config := { foApprox := false, ctxApprox := false, quasiPatternApprox := false, constApprox := false, isDefEqStuckEx := false, unificationHints := true, proofIrrelevance := true, assignSyntheticOpaque := false, offsetCnstrs := true, transparency := Lean.Meta.TransparencyMode.default, trackZetaDelta := false, etaStruct := Lean.Meta.EtaStructMode.all }, lctx := { fvarIdToDecl := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }, localInstances := #[], defEqCtx? := none, synthPendingDepth := 0, canUnfold? := none }) (s : optParam Lean.Meta.State { mctx := { depth := 0, levelAssignDepth := 0, mvarCounter := 0, lDepth := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, userNames := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, lAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, eAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, dAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, cache := { inferType := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, funInfo := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, synthInstance := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfDefault := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfAll := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, defEqTrans := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, defEqPerm := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } } }, zetaDeltaFVarIds := , postponed := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }) :
                            Equations
                            Instances For
                              @[inline]
                              def Lean.Meta.MetaM.run' {α : Type} (x : Lean.MetaM α) (ctx : optParam Lean.Meta.Context { config := { foApprox := false, ctxApprox := false, quasiPatternApprox := false, constApprox := false, isDefEqStuckEx := false, unificationHints := true, proofIrrelevance := true, assignSyntheticOpaque := false, offsetCnstrs := true, transparency := Lean.Meta.TransparencyMode.default, trackZetaDelta := false, etaStruct := Lean.Meta.EtaStructMode.all }, lctx := { fvarIdToDecl := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }, localInstances := #[], defEqCtx? := none, synthPendingDepth := 0, canUnfold? := none }) (s : optParam Lean.Meta.State { mctx := { depth := 0, levelAssignDepth := 0, mvarCounter := 0, lDepth := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, userNames := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, lAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, eAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, dAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, cache := { inferType := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, funInfo := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, synthInstance := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfDefault := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfAll := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, defEqTrans := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, defEqPerm := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } } }, zetaDeltaFVarIds := , postponed := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }) :
                              Equations
                              Instances For
                                @[inline]
                                def Lean.Meta.MetaM.toIO {α : Type} (x : Lean.MetaM α) (ctxCore : Lean.Core.Context) (sCore : Lean.Core.State) (ctx : optParam Lean.Meta.Context { config := { foApprox := false, ctxApprox := false, quasiPatternApprox := false, constApprox := false, isDefEqStuckEx := false, unificationHints := true, proofIrrelevance := true, assignSyntheticOpaque := false, offsetCnstrs := true, transparency := Lean.Meta.TransparencyMode.default, trackZetaDelta := false, etaStruct := Lean.Meta.EtaStructMode.all }, lctx := { fvarIdToDecl := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }, localInstances := #[], defEqCtx? := none, synthPendingDepth := 0, canUnfold? := none }) (s : optParam Lean.Meta.State { mctx := { depth := 0, levelAssignDepth := 0, mvarCounter := 0, lDepth := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, decls := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, userNames := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, lAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, eAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, dAssignment := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, cache := { inferType := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, funInfo := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, synthInstance := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfDefault := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, whnfAll := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, defEqTrans := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } }, defEqPerm := { reducible := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, instances := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, default := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 }, all := { root := Lean.PersistentHashMap.Node.entries Lean.PersistentHashMap.mkEmptyEntriesArray, size := 0 } } }, zetaDeltaFVarIds := , postponed := { root := Lean.PersistentArrayNode.node (Array.mkEmpty (USize.toNat Lean.PersistentArray.branching)), tail := Array.mkEmpty (USize.toNat Lean.PersistentArray.branching), size := 0, shift := Lean.PersistentArray.initShift, tailOff := 0 } }) :
                                Equations
                                Instances For
                                  Equations
                                  • One or more equations did not get rendered due to their size.
                                  @[inline]
                                  def Lean.Meta.liftMetaM {m : TypeType u_1} {α : Type} [MonadLiftT Lean.MetaM m] (x : Lean.MetaM α) :
                                  m α
                                  Equations
                                  Instances For
                                    @[inline]
                                    def Lean.Meta.mapMetaM {m : TypeType u_1} [MonadControlT Lean.MetaM m] [Monad m] (f : {α : Type} → Lean.MetaM αLean.MetaM α) {α : Type} (x : m α) :
                                    m α
                                    Equations
                                    Instances For
                                      @[inline]
                                      def Lean.Meta.map1MetaM {m : TypeType u_1} {β : Sort u_2} [MonadControlT Lean.MetaM m] [Monad m] (f : {α : Type} → (βLean.MetaM α)Lean.MetaM α) {α : Type} (k : βm α) :
                                      m α
                                      Equations
                                      Instances For
                                        @[inline]
                                        def Lean.Meta.map2MetaM {m : TypeType u_1} {β : Sort u_2} {γ : Sort u_3} [MonadControlT Lean.MetaM m] [Monad m] (f : {α : Type} → (βγLean.MetaM α)Lean.MetaM α) {α : Type} (k : βγm α) :
                                        m α
                                        Equations
                                        Instances For
                                          @[inline]
                                          Equations
                                          • One or more equations did not get rendered due to their size.
                                          Instances For
                                            @[inline]
                                            Equations
                                            • One or more equations did not get rendered due to their size.
                                            Instances For
                                              @[inline]
                                              Equations
                                              • One or more equations did not get rendered due to their size.
                                              Instances For
                                                @[inline]
                                                Equations
                                                • One or more equations did not get rendered due to their size.
                                                Instances For
                                                  @[inline]
                                                  Equations
                                                  • One or more equations did not get rendered due to their size.
                                                  Instances For
                                                    Equations
                                                    Instances For
                                                      Equations
                                                      Instances For
                                                        Equations
                                                        Instances For
                                                          Equations
                                                          Instances For

                                                            Return the array of postponed universe level constraints.

                                                            Equations
                                                            Instances For

                                                              Set the array of postponed universe level constraints.

                                                              Equations
                                                              Instances For
                                                                @[inline]

                                                                Modify the array of postponed universe level constraints.

                                                                Equations
                                                                Instances For

                                                                  useEtaStruct inductName return true if we eta for structures is enabled for for the inductive datatype inductName.

                                                                  Recall we have three different settings: .none (never use it), .all (always use it), .notClasses (enabled only for structure-like inductive types that are not classes).

                                                                  The parameter inductName affects the result only if the current setting is .notClasses.

                                                                  Equations
                                                                  • One or more equations did not get rendered due to their size.
                                                                  Instances For

                                                                    WARNING: The following 4 constants are a hack for simulating forward declarations. They are defined later using the export attribute. This is hackish because we have to hard-code the true arity of these definitions here, and make sure the C names match. We have used another hack based on IO.Refs in the past, it was safer but less efficient.

                                                                    @[extern 6 lean_whnf]

                                                                    Reduces an expression to its Weak Head Normal Form. This is when the topmost expression has been fully reduced, but may contain subexpressions which have not been reduced.

                                                                    @[extern 6 lean_infer_type]

                                                                    Returns the inferred type of the given expression, or fails if it is not type-correct.

                                                                    @[extern 7 lean_is_expr_def_eq]
                                                                    @[extern 7 lean_is_level_def_eq]
                                                                    @[extern 6 lean_synth_pending]
                                                                    Equations
                                                                    Instances For
                                                                      def Lean.Meta.withIncRecDepth {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                      n α
                                                                      Equations
                                                                      Instances For
                                                                        Equations
                                                                        • One or more equations did not get rendered due to their size.
                                                                        Instances For
                                                                          Equations
                                                                          • One or more equations did not get rendered due to their size.
                                                                          Instances For
                                                                            Equations
                                                                            • One or more equations did not get rendered due to their size.
                                                                            Instances For
                                                                              Equations
                                                                              Instances For

                                                                                Create a constant with the given name and new universe metavariables. Example: mkConstWithFreshMVarLevels `Monad returns @Monad.{?u, ?v}

                                                                                Equations
                                                                                Instances For

                                                                                  Return current transparency setting/mode.

                                                                                  Equations
                                                                                  Instances For

                                                                                    Return some mvarDecl where mvarDecl is mvarId declaration in the current metavariable context. Return none if mvarId has no declaration in the current metavariable context.

                                                                                    Equations
                                                                                    Instances For
                                                                                      @[deprecated Lean.MVarId.findDecl?]
                                                                                      Equations
                                                                                      Instances For

                                                                                        Return mvarId declaration in the current metavariable context. Throw an exception if mvarId is not declared in the current metavariable context.

                                                                                        Equations
                                                                                        • One or more equations did not get rendered due to their size.
                                                                                        Instances For
                                                                                          @[deprecated Lean.MVarId.getDecl]
                                                                                          Equations
                                                                                          Instances For

                                                                                            Return mvarId kind. Throw an exception if mvarId is not declared in the current metavariable context.

                                                                                            Equations
                                                                                            Instances For
                                                                                              @[deprecated Lean.MVarId.getKind]
                                                                                              Equations
                                                                                              Instances For

                                                                                                Return true if e is a synthetic (or synthetic opaque) metavariable

                                                                                                Equations
                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                Instances For

                                                                                                  Set mvarId kind in the current metavariable context.

                                                                                                  Equations
                                                                                                  Instances For
                                                                                                    @[deprecated Lean.MVarId.setKind]
                                                                                                    Equations
                                                                                                    Instances For

                                                                                                      Update the type of the given metavariable. This function assumes the new type is definitionally equal to the current one

                                                                                                      Equations
                                                                                                      Instances For
                                                                                                        @[deprecated Lean.MVarId.setType]
                                                                                                        Equations
                                                                                                        Instances For

                                                                                                          Return true if the given metavariable is "read-only". That is, its depth is different from the current metavariable context depth.

                                                                                                          Equations
                                                                                                          Instances For
                                                                                                            @[deprecated Lean.MVarId.isReadOnly]
                                                                                                            Equations
                                                                                                            Instances For

                                                                                                              Return true if mvarId.isReadOnly return true or if mvarId is a synthetic opaque metavariable.

                                                                                                              Recall isDefEq will not assign a value to mvarId if mvarId.isReadOnlyOrSyntheticOpaque.

                                                                                                              Equations
                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                              Instances For
                                                                                                                @[deprecated Lean.MVarId.isReadOnlyOrSyntheticOpaque]
                                                                                                                Equations
                                                                                                                Instances For

                                                                                                                  Return the level of the given universe level metavariable.

                                                                                                                  Equations
                                                                                                                  • One or more equations did not get rendered due to their size.
                                                                                                                  Instances For
                                                                                                                    @[deprecated Lean.LMVarId.getLevel]
                                                                                                                    Equations
                                                                                                                    Instances For

                                                                                                                      Return true if the given universe metavariable is "read-only". That is, its depth is different from the current metavariable context depth.

                                                                                                                      Equations
                                                                                                                      Instances For
                                                                                                                        @[deprecated Lean.LMVarId.isReadOnly]
                                                                                                                        Equations
                                                                                                                        Instances For

                                                                                                                          Set the user-facing name for the given metavariable.

                                                                                                                          Equations
                                                                                                                          Instances For
                                                                                                                            @[deprecated Lean.MVarId.setUserName]
                                                                                                                            Equations
                                                                                                                            Instances For

                                                                                                                              Throw an exception saying fvarId is not declared in the current local context.

                                                                                                                              Equations
                                                                                                                              Instances For
                                                                                                                                @[deprecated Lean.FVarId.throwUnknown]
                                                                                                                                Equations
                                                                                                                                Instances For

                                                                                                                                  Return some decl if fvarId is declared in the current local context.

                                                                                                                                  Equations
                                                                                                                                  Instances For
                                                                                                                                    @[deprecated Lean.FVarId.findDecl?]
                                                                                                                                    Equations
                                                                                                                                    Instances For

                                                                                                                                      Return the local declaration for the given free variable. Throw an exception if local declaration is not in the current local context.

                                                                                                                                      Equations
                                                                                                                                      Instances For
                                                                                                                                        @[deprecated Lean.FVarId.getDecl]
                                                                                                                                        Equations
                                                                                                                                        Instances For

                                                                                                                                          Return the type of the given free variable.

                                                                                                                                          Equations
                                                                                                                                          Instances For

                                                                                                                                            Return the binder information for the given free variable.

                                                                                                                                            Equations
                                                                                                                                            Instances For

                                                                                                                                              Return some value if the given free variable is a let-declaration, and none otherwise.

                                                                                                                                              Equations
                                                                                                                                              Instances For

                                                                                                                                                Return the user-facing name for the given free variable.

                                                                                                                                                Equations
                                                                                                                                                Instances For

                                                                                                                                                  Return true is the free variable is a let-variable.

                                                                                                                                                  Equations
                                                                                                                                                  Instances For

                                                                                                                                                    Get the local declaration associated to the given Expr in the current local context. Fails if the given expression is not a fvar or if no such declaration exists.

                                                                                                                                                    Equations
                                                                                                                                                    Instances For

                                                                                                                                                      Given a user-facing name for a free variable, return its declaration in the current local context. Throw an exception if free variable is not declared.

                                                                                                                                                      Equations
                                                                                                                                                      • One or more equations did not get rendered due to their size.
                                                                                                                                                      Instances For

                                                                                                                                                        Given a user-facing name for a free variable, return the free variable or throw if not declared.

                                                                                                                                                        Equations
                                                                                                                                                        Instances For
                                                                                                                                                          @[inline]

                                                                                                                                                          Lift a MkBindingM monadic action x to MetaM.

                                                                                                                                                          Equations
                                                                                                                                                          • One or more equations did not get rendered due to their size.
                                                                                                                                                          Instances For

                                                                                                                                                            Similar to abstracM but consider only the first min n xs.size entries in xs

                                                                                                                                                            It is also similar to Expr.abstractRange, but handles metavariables correctly. It uses elimMVarDeps to ensure e and the type of the free variables xs do not contain a metavariable ?m s.t. local context of ?m contains a free variable in xs.

                                                                                                                                                            Equations
                                                                                                                                                            Instances For
                                                                                                                                                              @[deprecated Lean.Expr.abstractRangeM]
                                                                                                                                                              Equations
                                                                                                                                                              Instances For

                                                                                                                                                                Replace free (or meta) variables xs with loose bound variables. Similar to Expr.abstract, but handles metavariables correctly.

                                                                                                                                                                Equations
                                                                                                                                                                Instances For
                                                                                                                                                                  @[deprecated Lean.Expr.abstractM]
                                                                                                                                                                  Equations
                                                                                                                                                                  Instances For

                                                                                                                                                                    Collect forward dependencies for the free variables in toRevert. Recall that when reverting free variables xs, we must also revert their forward dependencies.

                                                                                                                                                                    Equations
                                                                                                                                                                    Instances For

                                                                                                                                                                      Takes an array xs of free variables or metavariables and a term e that may contain those variables, and abstracts and binds them as universal quantifiers.

                                                                                                                                                                      • if usedOnly = true then only variables that the expression body depends on will appear.
                                                                                                                                                                      • if usedLetOnly = true same as usedOnly except for let-bound variables. (That is, local constants which have been assigned a value.)
                                                                                                                                                                      Equations
                                                                                                                                                                      • One or more equations did not get rendered due to their size.
                                                                                                                                                                      Instances For

                                                                                                                                                                        Takes an array xs of free variables and metavariables and a body term e and creates fun ..xs => e, suitably abstracting e and the types in xs.

                                                                                                                                                                        Equations
                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                        Instances For
                                                                                                                                                                          Equations
                                                                                                                                                                          Instances For

                                                                                                                                                                            fun _ : Unit => a

                                                                                                                                                                            Equations
                                                                                                                                                                            Instances For
                                                                                                                                                                              Equations
                                                                                                                                                                              Instances For
                                                                                                                                                                                @[inline]
                                                                                                                                                                                def Lean.Meta.withConfig {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (f : Lean.Meta.ConfigLean.Meta.Config) :
                                                                                                                                                                                n αn α

                                                                                                                                                                                withConfig f x executes x using the updated configuration object obtained by applying f.

                                                                                                                                                                                Equations
                                                                                                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                                                                                                Instances For
                                                                                                                                                                                  @[inline]
                                                                                                                                                                                  def Lean.Meta.withTrackingZetaDelta {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                  n α

                                                                                                                                                                                  Executes x tracking zetaDelta reductions Config.trackZetaDelta := true

                                                                                                                                                                                  Equations
                                                                                                                                                                                  • One or more equations did not get rendered due to their size.
                                                                                                                                                                                  Instances For
                                                                                                                                                                                    @[inline]
                                                                                                                                                                                    def Lean.Meta.withoutProofIrrelevance {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                    n α
                                                                                                                                                                                    Equations
                                                                                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                                                                                    Instances For
                                                                                                                                                                                      @[inline]
                                                                                                                                                                                      def Lean.Meta.withTransparency {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (mode : Lean.Meta.TransparencyMode) :
                                                                                                                                                                                      n αn α
                                                                                                                                                                                      Equations
                                                                                                                                                                                      • One or more equations did not get rendered due to their size.
                                                                                                                                                                                      Instances For
                                                                                                                                                                                        @[inline]
                                                                                                                                                                                        def Lean.Meta.withDefault {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                        n α

                                                                                                                                                                                        withDefault x executes x using the default transparency setting.

                                                                                                                                                                                        Equations
                                                                                                                                                                                        Instances For
                                                                                                                                                                                          @[inline]
                                                                                                                                                                                          def Lean.Meta.withReducible {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                          n α

                                                                                                                                                                                          withReducible x executes x using the reducible transparency setting. In this setting only definitions tagged as [reducible] are unfolded.

                                                                                                                                                                                          Equations
                                                                                                                                                                                          Instances For
                                                                                                                                                                                            @[inline]
                                                                                                                                                                                            def Lean.Meta.withReducibleAndInstances {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                            n α

                                                                                                                                                                                            withReducibleAndInstances x executes x using the .instances transparency setting. In this setting only definitions tagged as [reducible] or type class instances are unfolded.

                                                                                                                                                                                            Equations
                                                                                                                                                                                            Instances For
                                                                                                                                                                                              @[inline]
                                                                                                                                                                                              def Lean.Meta.withAtLeastTransparency {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (mode : Lean.Meta.TransparencyMode) (x : n α) :
                                                                                                                                                                                              n α

                                                                                                                                                                                              Execute x ensuring the transparency setting is at least mode. Recall that .all > .default > .instances > .reducible.

                                                                                                                                                                                              Equations
                                                                                                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                                                                                                              Instances For
                                                                                                                                                                                                @[inline]
                                                                                                                                                                                                def Lean.Meta.withAssignableSyntheticOpaque {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (x : n α) :
                                                                                                                                                                                                n α

                                                                                                                                                                                                Execute x allowing isDefEq to assign synthetic opaque metavariables.

                                                                                                                                                                                                Equations
                                                                                                                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                Instances For
                                                                                                                                                                                                  @[inline]
                                                                                                                                                                                                  def Lean.Meta.savingCache {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} :
                                                                                                                                                                                                  n αn α
                                                                                                                                                                                                  Equations
                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                    Equations
                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                      def Lean.Meta.withNewLocalInstance {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (className : Lake.Name) (fvar : Lean.Expr) :
                                                                                                                                                                                                      n αn α

                                                                                                                                                                                                      Add entry { className := className, fvar := fvar } to localInstances, and then execute continuation k.

                                                                                                                                                                                                      Equations
                                                                                                                                                                                                      Instances For

                                                                                                                                                                                                        isClass? type return some ClsName if type is an instance of the class ClsName. Example:

                                                                                                                                                                                                        #eval do
                                                                                                                                                                                                          let x ← mkAppM ``Inhabited #[mkConst ``Nat]
                                                                                                                                                                                                          IO.println (← isClass? x)
                                                                                                                                                                                                          -- (some Inhabited)
                                                                                                                                                                                                        
                                                                                                                                                                                                        Equations
                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                          def Lean.Meta.withNewLocalInstances {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (fvars : Array Lean.Expr) (j : Nat) :
                                                                                                                                                                                                          n αn α
                                                                                                                                                                                                          Equations
                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                            def Lean.Meta.forallTelescope {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (type : Lean.Expr) (k : Array Lean.ExprLean.Exprn α) :
                                                                                                                                                                                                            n α

                                                                                                                                                                                                            Given type of the form forall xs, A, execute k xs A. This combinator will declare local declarations, create free variables for them, execute k with updated local context, and make sure the cache is restored after executing k.

                                                                                                                                                                                                            Equations
                                                                                                                                                                                                            Instances For

                                                                                                                                                                                                              Given a monadic function f that takes a type and a term of that type and produces a new term, lifts this to the monadic function that opens a telescope, applies f to the body, and then builds the lambda telescope term for the new term.

                                                                                                                                                                                                              Equations
                                                                                                                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                              Instances For

                                                                                                                                                                                                                Given a monadic function f that takes a term and produces a new term, lifts this to the monadic function that opens a telescope, applies f to the body, and then builds the lambda telescope term for the new term.

                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                  def Lean.Meta.forallTelescopeReducing {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (type : Lean.Expr) (k : Array Lean.ExprLean.Exprn α) :
                                                                                                                                                                                                                  n α

                                                                                                                                                                                                                  Similar to forallTelescope, but given type of the form forall xs, A, it reduces A and continues building the telescope if it is a forall.

                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                    def Lean.Meta.forallBoundedTelescope {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (type : Lean.Expr) (maxFVars? : Option Nat) (k : Array Lean.ExprLean.Exprn α) :
                                                                                                                                                                                                                    n α

                                                                                                                                                                                                                    Similar to forallTelescopeReducing, stops constructing the telescope when it reaches size maxFVars.

                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                      def Lean.Meta.lambdaLetTelescope {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (e : Lean.Expr) (k : Array Lean.ExprLean.Exprn α) (cleanupAnnotations : optParam Bool false) :
                                                                                                                                                                                                                      n α

                                                                                                                                                                                                                      Similar to lambdaTelescope but for lambda and let expressions.

                                                                                                                                                                                                                      If cleanupAnnotations is true, we apply Expr.cleanupAnnotations to each type in the telescope.

                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                      • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                        def Lean.Meta.lambdaTelescope {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (e : Lean.Expr) (k : Array Lean.ExprLean.Exprn α) (cleanupAnnotations : optParam Bool false) :
                                                                                                                                                                                                                        n α

                                                                                                                                                                                                                        Given e of the form fun ..xs => A, execute k xs A. This combinator will declare local declarations, create free variables for them, execute k with updated local context, and make sure the cache is restored after executing k.

                                                                                                                                                                                                                        If cleanupAnnotations is true, we apply Expr.cleanupAnnotations to each type in the telescope.

                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                        Instances For

                                                                                                                                                                                                                          Return the parameter names for the given global declaration.

                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                          • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                          Instances For

                                                                                                                                                                                                                            Given e of the form forall ..xs, A, this combinator will create a new metavariable for each x in xs and instantiate A with these. Returns a product containing

                                                                                                                                                                                                                            • the new metavariables
                                                                                                                                                                                                                            • the binder info for the xs
                                                                                                                                                                                                                            • the instantiated A
                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                            Instances For

                                                                                                                                                                                                                              Similar to forallMetaTelescope, but if e = forall ..xs, A it will reduce A to construct further mvars.

                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                              Instances For

                                                                                                                                                                                                                                Similar to forallMetaTelescopeReducing, stops constructing the telescope when it reaches size maxMVars.

                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                Instances For

                                                                                                                                                                                                                                  Similar to forallMetaTelescopeReducingAux but for lambda expressions.

                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                  Instances For

                                                                                                                                                                                                                                    Create a free variable x with name, binderInfo and type, add it to the context and run in k. Then revert the context.

                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                                      def Lean.Meta.withLocalDeclD {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (name : Lake.Name) (type : Lean.Expr) (k : Lean.Exprn α) :
                                                                                                                                                                                                                                      n α
                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                                        def Lean.Meta.withLocalDecls {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} [Inhabited α] (declInfos : Array (Lake.Name × Lean.BinderInfo × (Array Lean.Exprn Lean.Expr))) (k : Array Lean.Exprn α) :
                                                                                                                                                                                                                                        n α

                                                                                                                                                                                                                                        Append an array of free variables xs to the local context and execute k xs. declInfos takes the form of an array consisting of:

                                                                                                                                                                                                                                        • the name of the variable
                                                                                                                                                                                                                                        • the binder info of the variable
                                                                                                                                                                                                                                        • a type constructor for the variable, where the array consists of all of the free variables defined prior to this one. This is needed because the type of the variable may depend on prior variables.
                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                                          partial def Lean.Meta.withLocalDecls.loop {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (declInfos : Array (Lake.Name × Lean.BinderInfo × (Array Lean.Exprn Lean.Expr))) (k : Array Lean.Exprn α) [Inhabited α] (acc : Array Lean.Expr) :
                                                                                                                                                                                                                                          n α
                                                                                                                                                                                                                                          def Lean.Meta.withLocalDeclsD {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} [Inhabited α] (declInfos : Array (Lake.Name × (Array Lean.Exprn Lean.Expr))) (k : Array Lean.Exprn α) :
                                                                                                                                                                                                                                          n α
                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                          • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                                            def Lean.Meta.withNewBinderInfos {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (bs : Array (Lean.FVarId × Lean.BinderInfo)) (k : n α) :
                                                                                                                                                                                                                                            n α
                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                            Instances For

                                                                                                                                                                                                                                              Execute k using a local context where any x in xs that is tagged as instance implicit is treated as a regular implicit.

                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                                def Lean.Meta.withLetDecl {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (name : Lake.Name) (type : Lean.Expr) (val : Lean.Expr) (k : Lean.Exprn α) (kind : optParam Lean.LocalDeclKind Lean.LocalDeclKind.default) :
                                                                                                                                                                                                                                                n α

                                                                                                                                                                                                                                                Add the local declaration <name> : <type> := <val> to the local context and execute k x, where x is a new free variable corresponding to the let-declaration. After executing k x, the local context is restored.

                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                  • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                                    def Lean.Meta.withLocalInstances {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (decls : List Lean.LocalDecl) :
                                                                                                                                                                                                                                                    n αn α

                                                                                                                                                                                                                                                    Register any local instance in decls

                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                                                      def Lean.Meta.withExistingLocalDecls {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (decls : List Lean.LocalDecl) :
                                                                                                                                                                                                                                                      n αn α

                                                                                                                                                                                                                                                      withExistingLocalDecls decls k, adds the given local declarations to the local context, and then executes k. This method assumes declarations in decls have valid FVarIds. After executing k, the local context is restored.

                                                                                                                                                                                                                                                      Remark: this method is used, for example, to implement the match-compiler. Each match-alternative commes with a local declarations (corresponding to pattern variables), and we use withExistingLocalDecls to add them to the local context before we process them.

                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                                                        def Lean.Meta.withNewMCtxDepth {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (k : n α) (allowLevelAssignments : optParam Bool false) :
                                                                                                                                                                                                                                                        n α

                                                                                                                                                                                                                                                        withNewMCtxDepth k executes k with a higher metavariable context depth, where metavariables created outside the withNewMCtxDepth (with a lower depth) cannot be assigned. If allowLevelAssignments is set to true, then the level metavariable depth is not increased, and level metavariables from the outer scope can be assigned. (This is used by TC synthesis.)

                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                                                          def Lean.Meta.withLCtx {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (lctx : Lean.LocalContext) (localInsts : Lean.LocalInstances) :
                                                                                                                                                                                                                                                          n αn α

                                                                                                                                                                                                                                                          withLCtx lctx localInsts k replaces the local context and local instances, and then executes k. The local context and instances are restored after executing k. This method assumes that the local instances in localInsts are in the local context lctx.

                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                                                            def Lean.MVarId.withContext {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (mvarId : Lean.MVarId) :
                                                                                                                                                                                                                                                            n αn α

                                                                                                                                                                                                                                                            Execute x using the given metavariable LocalContext and LocalInstances. The type class resolution cache is flushed when executing x if its LocalInstances are different from the current ones.

                                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                                                              @[deprecated Lean.MVarId.withContext]
                                                                                                                                                                                                                                                              def Lean.Meta.withMVarContext {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (mvarId : Lean.MVarId) :
                                                                                                                                                                                                                                                              n αn α
                                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                                                def Lean.Meta.withMCtx {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} (mctx : Lean.MetavarContext) :
                                                                                                                                                                                                                                                                n αn α

                                                                                                                                                                                                                                                                withMCtx mctx k replaces the metavariable context and then executes k. The metavariable context is restored after executing k.

                                                                                                                                                                                                                                                                This method is used to implement the type class resolution procedure.

                                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                                                  @[inline]
                                                                                                                                                                                                                                                                  def Lean.Meta.approxDefEq {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} :
                                                                                                                                                                                                                                                                  n αn α

                                                                                                                                                                                                                                                                  Execute x using approximate unification: foApprox, ctxApprox and quasiPatternApprox.

                                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                                                    @[inline]
                                                                                                                                                                                                                                                                    def Lean.Meta.fullApproxDefEq {n : TypeType u_1} [MonadControlT Lean.MetaM n] [Monad n] {α : Type} :
                                                                                                                                                                                                                                                                    n αn α

                                                                                                                                                                                                                                                                    Similar to approxDefEq, but uses all available approximations. We don't use constApprox by default at approxDefEq because it often produces undesirable solution for monadic code. For example, suppose we have pure (x > 0) which has type ?m Prop. We also have the goal [Pure ?m]. Now, assume the expected type is IO Bool. Then, the unification constraint ?m Prop =?= IO Bool could be solved as ?m := fun _ => IO Bool using constApprox, but this spurious solution would generate a failure when we try to solve [Pure (fun _ => IO Bool)]

                                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                                    Instances For

                                                                                                                                                                                                                                                                      Instantiate assigned universe metavariables in u, and then normalize it.

                                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                                      Instances For

                                                                                                                                                                                                                                                                        Mark declaration declName with the attribute [inline]. This method does not check whether the given declaration is a definition.

                                                                                                                                                                                                                                                                        Recall that this attribute can only be set in the same module where declName has been declared.

                                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                        Instances For

                                                                                                                                                                                                                                                                          Given e of the form forall (a_1 : A_1) ... (a_n : A_n), B[a_1, ..., a_n] and p_1 : A_1, ... p_n : A_n, return B[p_1, ..., p_n].

                                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                                          Instances For

                                                                                                                                                                                                                                                                            Given e of the form fun (a_1 : A_1) ... (a_n : A_n) => t[a_1, ..., a_n] and p_1 : A_1, ... p_n : A_n, return t[p_1, ..., p_n]. It uses whnf to reduce e if it is not a lambda

                                                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                                                            Instances For

                                                                                                                                                                                                                                                                              Pretty-print the given expression.

                                                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                              Instances For

                                                                                                                                                                                                                                                                                Pretty-print the given expression.

                                                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                                                                  @[inline]
                                                                                                                                                                                                                                                                                  def Lean.Meta.orElse {α : Type} (x : Lean.MetaM α) (y : UnitLean.MetaM α) :
                                                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                                                    • Lean.Meta.instOrElseMetaM = { orElse := Lean.Meta.orElse }
                                                                                                                                                                                                                                                                                    @[inline]

                                                                                                                                                                                                                                                                                    Similar to orelse, but merge errors. Note that internal errors are not caught. The default mergeRef uses the ref (position information) for the first message. The default mergeMsg combines error messages using Format.line ++ Format.line as a separator.

                                                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                    Instances For

                                                                                                                                                                                                                                                                                      Execute x, and apply f to the produced error message

                                                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                                                                                        @[inline]
                                                                                                                                                                                                                                                                                        def Lean.Meta.mapError {m : TypeType u_1} {α : Type} [MonadControlT Lean.MetaM m] [Monad m] (x : m α) (f : Lean.MessageDataLean.MessageData) :
                                                                                                                                                                                                                                                                                        m α
                                                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                                                        Instances For

                                                                                                                                                                                                                                                                                          Sort free variables using an order x < y iff x was defined before y. If a free variable is not in the local context, we use their id.

                                                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                                                          • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                          Instances For

                                                                                                                                                                                                                                                                                            Return true if declName is an inductive predicate. That is, inductive type in Prop.

                                                                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                                                                            • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                                                                                  def Lean.Meta.processPostponed (mayPostpone : optParam Bool true) (exceptionOnFailure : optParam Bool false) :
                                                                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                                                                  • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                                                                                    partial def Lean.Meta.processPostponed.loop (mayPostpone : optParam Bool true) (exceptionOnFailure : optParam Bool false) :
                                                                                                                                                                                                                                                                                                    @[specialize #[]]

                                                                                                                                                                                                                                                                                                    checkpointDefEq x executes x and process all postponed universe level constraints produced by x. We keep the modifications only if processPostponed return true and x returned true.

                                                                                                                                                                                                                                                                                                    If mayPostpone == false, all new postponed universe level constraints must be solved before returning. We currently try to postpone universe constraints as much as possible, even when by postponing them we are not sure whether x really succeeded or not.

                                                                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                    Instances For

                                                                                                                                                                                                                                                                                                      Determines whether two universe level expressions are definitionally equal to each other.

                                                                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                                                                      Instances For

                                                                                                                                                                                                                                                                                                        See isDefEq.

                                                                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                                                                                                          @[inline, reducible]

                                                                                                                                                                                                                                                                                                          Determines whether two expressions are definitionally equal to each other.

                                                                                                                                                                                                                                                                                                          To control how metavariables are assigned and unified, metavariables and their context have a "depth". Given a metavariable ?m and a MetavarContext mctx, ?m is not assigned if ?m.depth != mctx.depth. The combinator withNewMCtxDepth x will bump the depth while executing x. So, withNewMCtxDepth (isDefEq a b) is isDefEq without any mvar assignment happening whereas isDefEq a b will assign any metavariables of the current depth in a and b to unify them.

                                                                                                                                                                                                                                                                                                          For matching (where only mvars in b should be assigned), we create the term inside the withNewMCtxDepth. For an example, see Lean.Meta.Simp.tryTheoremWithExtraArgs?

                                                                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                                                                                            • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                                                                                                              @[inline, reducible]

                                                                                                                                                                                                                                                                                                              Similar to isDefEq, but returns false if an exception has been thrown.

                                                                                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                                                                                              Instances For

                                                                                                                                                                                                                                                                                                                Eta expand the given expression. Example:

                                                                                                                                                                                                                                                                                                                etaExpand (mkConst ``Nat.add)
                                                                                                                                                                                                                                                                                                                

                                                                                                                                                                                                                                                                                                                produces fun x y => Nat.add x y

                                                                                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                                                                Instances For

                                                                                                                                                                                                                                                                                                                  If e is of the form ?m ... instantiate metavars

                                                                                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                                                                                  Instances For