lean4-htt/src/Lean/Meta/Match/MatchEqsExt.lean

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/-
Copyright (c) 2022 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura
-/
prelude
import Lean.Meta.Basic
namespace Lean.Meta.Match
structure MatchEqns where
eqnNames : Array Name
splitterName : Name
splitterAltNumParams : Array Nat
deriving Inhabited, Repr
def MatchEqns.size (e : MatchEqns) : Nat :=
e.eqnNames.size
structure MatchEqnsExtState where
map : PHashMap Name MatchEqns := {}
eqns : PHashSet Name := {}
deriving Inhabited
/- We generate the equations and splitter on demand, and do not save them on .olean files. -/
builtin_initialize matchEqnsExt : EnvExtension MatchEqnsExtState ←
registerEnvExtension (pure {})
def registerMatchEqns (matchDeclName : Name) (matchEqns : MatchEqns) : CoreM Unit := do
modifyEnv fun env => matchEqnsExt.modifyState env fun { map, eqns } => {
eqns := matchEqns.eqnNames.foldl (init := eqns) fun eqns eqn => eqns.insert eqn
map := map.insert matchDeclName matchEqns
}
/-
Forward definition. We want to use `getEquationsFor` in the simplifier,
`getEquationsFor` depends on `mkEquationsfor` which uses the simplifier. -/
@[extern "lean_get_match_equations_for"]
opaque getEquationsFor (matchDeclName : Name) : MetaM MatchEqns
/--
Returns `true` if `declName` is the name of a `match` equational theorem.
-/
def isMatchEqnTheorem (env : Environment) (declName : Name) : Bool :=
matchEqnsExt.getState env |>.eqns.contains declName
end Lean.Meta.Match