lean4-htt/src/Init/Lean/Elab/DeclModifiers.lean
2020-01-10 19:51:53 -08:00

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/-
Copyright (c) 2020 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura, Sebastian Ullrich
-/
prelude
import Init.Lean.Elab.Command
namespace Lean
namespace Elab
namespace Command
structure Attribute :=
(name : Name) (args : Syntax := Syntax.missing)
instance Attribute.hasFormat : HasFormat Attribute :=
⟨fun attr => Format.bracket "@[" (toString attr.name ++ (if attr.args.isMissing then "" else toString attr.args)) "]"⟩
inductive Visibility
| regular | «protected» | «private»
instance Visibility.hasToString : HasToString Visibility :=
⟨fun v => match v with
| Visibility.regular => "regular"
| Visibility.private => "private"
| Visibility.protected => "protected"⟩
structure Modifiers :=
(docString : Option String := none)
(visibility : Visibility := Visibility.regular)
(isNoncomputable : Bool := false)
(isPartial : Bool := false)
(isUnsafe : Bool := false)
(attrs : Array Attribute := #[])
def Modifiers.addAttribute (modifiers : Modifiers) (attr : Attribute) : Modifiers :=
{ attrs := modifiers.attrs.push attr, .. modifiers }
instance Modifiers.hasFormat : HasFormat Modifiers :=
⟨fun m =>
let components : List Format :=
(match m.docString with
| some str => ["/--" ++ str ++ "-/"]
| none => [])
++ (match m.visibility with
| Visibility.regular => []
| Visibility.protected => ["protected"]
| Visibility.private => ["private"])
++ (if m.isNoncomputable then ["noncomputable"] else [])
++ (if m.isPartial then ["partial"] else [])
++ (if m.isUnsafe then ["unsafe"] else [])
++ m.attrs.toList.map (fun attr => fmt attr);
Format.bracket "{" (Format.joinSep components ("," ++ Format.line)) "}"⟩
instance Modifiers.hasToString : HasToString Modifiers := ⟨toString ∘ format⟩
def elabAttr (stx : Syntax) : CommandElabM Attribute := do
-- rawIdent >> many attrArg
let nameStx := stx.getArg 0;
attrName ← match nameStx.isIdOrAtom? with
| none => throwError nameStx "identifier expected"
| some str => pure $ mkNameSimple str;
env ← getEnv;
unless (isAttribute env attrName) $
throwError stx ("unknown attribute [" ++ attrName ++ "]");
let args := stx.getArg 1;
pure { name := attrName, args := args }
def elabAttrs (stx : Syntax) : CommandElabM (Array Attribute) :=
(stx.getArg 1).foldSepArgsM
(fun stx attrs => do
attr ← elabAttr stx;
pure $ attrs.push attr)
#[]
def elabModifiers (stx : Syntax) : CommandElabM Modifiers := do
let docCommentStx := stx.getArg 0;
let attrsStx := stx.getArg 1;
let visibilityStx := stx.getArg 2;
let noncompStx := stx.getArg 3;
let unsafeStx := stx.getArg 4;
let partialStx := stx.getArg 5;
docString ← match docCommentStx.getOptional? with
| none => pure none
| some s => match s.getArg 1 with
| Syntax.atom _ val => pure (some (val.extract 0 (val.bsize - 2)))
| _ => throwError s ("unexpected doc string " ++ toString (s.getArg 1));
visibility ← match visibilityStx.getOptional? with
| none => pure Visibility.regular
| some v =>
let kind := v.getKind;
if kind == `Lean.Parser.Command.private then pure Visibility.private
else if kind == `Lean.Parser.Command.protected then pure Visibility.protected
else throwError v "unexpected visibility modifier";
attrs ← match attrsStx.getOptional? with
| none => pure #[]
| some attrs => elabAttrs attrs;
pure {
docString := docString,
visibility := visibility,
isPartial := !partialStx.isNone,
isUnsafe := !unsafeStx.isNone,
isNoncomputable := !noncompStx.isNone,
attrs := attrs
}
def mkDeclName (modifiers : Modifiers) (atomicName : Name) : CommandElabM Name := do
currNamespace ← getCurrNamespace;
let declName := currNamespace ++ atomicName;
match modifiers.visibility with
| Visibility.private => do
env ← getEnv;
let (env, declName) := mkPrivateName env declName;
setEnv env;
-- TODO: alias?
pure declName
| _ => pure declName
def applyAttributes (ref : Syntax) (declName : Name) (attrs : Array Attribute) (applicationTime : AttributeApplicationTime) : CommandElabM Unit :=
attrs.forM $ fun attr => do
env ← getEnv;
match getAttributeImpl env attr.name with
| Except.error errMsg => throwError ref errMsg
| Except.ok attrImpl =>
when (attrImpl.applicationTime == applicationTime) $ do
env ← getEnv;
env ← liftIO ref $ attrImpl.add env declName attr.args true;
setEnv env
end Command
end Elab
end Lean