40 lines
1.2 KiB
Text
40 lines
1.2 KiB
Text
/-
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Copyright (c) 2019 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Authors: Leonardo de Moura
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-/
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import Lean.Environment
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namespace Lean
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/- We use aliases to implement the `export <id> (<id>+)` command. -/
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abbrev AliasState := SMap Name (List Name)
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abbrev AliasEntry := Name × Name
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def addAliasEntry (s : AliasState) (e : AliasEntry) : AliasState :=
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match s.find? e.1 with
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| none => s.insert e.1 [e.2]
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| some es => if es.elem e.2 then s else s.insert e.1 (e.2 :: es)
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def mkAliasExtension : IO (SimplePersistentEnvExtension AliasEntry AliasState) :=
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registerSimplePersistentEnvExtension {
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name := `aliasesExt,
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addEntryFn := addAliasEntry,
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addImportedFn := fun es => (mkStateFromImportedEntries addAliasEntry {} es).switch
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}
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@[init mkAliasExtension]
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constant aliasExtension : SimplePersistentEnvExtension AliasEntry AliasState := arbitrary _
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/- Add alias `a` for `e` -/
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@[export lean_add_alias]
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def addAlias (env : Environment) (a : Name) (e : Name) : Environment :=
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aliasExtension.addEntry env (a, e)
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def getAliases (env : Environment) (a : Name) : List Name :=
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match (aliasExtension.getState env).find? a with
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| none => []
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| some es => es
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end Lean
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