35 lines
1.1 KiB
Text
35 lines
1.1 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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prelude
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import init.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 Name Name.quickLt
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abbrev AliasEntry := Name × Name
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def addAliasEntry (s : AliasState) (e : AliasEntry) : AliasState := s.insert e.1 e.2
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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 := default _
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/- Add alias `a` for `e` -/
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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 isAlias (env : Environment) (a : Name) : Option Name :=
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(aliasExtension.getState env).find a
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end Lean
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