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Diffstat (limited to 'src/pkg/go/ast/scope.go')
-rw-r--r-- | src/pkg/go/ast/scope.go | 162 |
1 files changed, 0 insertions, 162 deletions
diff --git a/src/pkg/go/ast/scope.go b/src/pkg/go/ast/scope.go deleted file mode 100644 index 8df5b2c65..000000000 --- a/src/pkg/go/ast/scope.go +++ /dev/null @@ -1,162 +0,0 @@ -// Copyright 2009 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// This file implements scopes and the objects they contain. - -package ast - -import ( - "bytes" - "fmt" - "go/token" -) - -// A Scope maintains the set of named language entities declared -// in the scope and a link to the immediately surrounding (outer) -// scope. -// -type Scope struct { - Outer *Scope - Objects map[string]*Object -} - -// NewScope creates a new scope nested in the outer scope. -func NewScope(outer *Scope) *Scope { - const n = 4 // initial scope capacity - return &Scope{outer, make(map[string]*Object, n)} -} - -// Lookup returns the object with the given name if it is -// found in scope s, otherwise it returns nil. Outer scopes -// are ignored. -// -func (s *Scope) Lookup(name string) *Object { - return s.Objects[name] -} - -// Insert attempts to insert a named object obj into the scope s. -// If the scope already contains an object alt with the same name, -// Insert leaves the scope unchanged and returns alt. Otherwise -// it inserts obj and returns nil." -// -func (s *Scope) Insert(obj *Object) (alt *Object) { - if alt = s.Objects[obj.Name]; alt == nil { - s.Objects[obj.Name] = obj - } - return -} - -// Debugging support -func (s *Scope) String() string { - var buf bytes.Buffer - fmt.Fprintf(&buf, "scope %p {", s) - if s != nil && len(s.Objects) > 0 { - fmt.Fprintln(&buf) - for _, obj := range s.Objects { - fmt.Fprintf(&buf, "\t%s %s\n", obj.Kind, obj.Name) - } - } - fmt.Fprintf(&buf, "}\n") - return buf.String() -} - -// ---------------------------------------------------------------------------- -// Objects - -// An Object describes a named language entity such as a package, -// constant, type, variable, function (incl. methods), or label. -// -// The Data fields contains object-specific data: -// -// Kind Data type Data value -// Pkg *types.Package package scope -// Con int iota for the respective declaration -// Con != nil constant value -// Typ *Scope (used as method scope during type checking - transient) -// -type Object struct { - Kind ObjKind - Name string // declared name - Decl interface{} // corresponding Field, XxxSpec, FuncDecl, LabeledStmt, AssignStmt, Scope; or nil - Data interface{} // object-specific data; or nil - Type interface{} // place holder for type information; may be nil -} - -// NewObj creates a new object of a given kind and name. -func NewObj(kind ObjKind, name string) *Object { - return &Object{Kind: kind, Name: name} -} - -// Pos computes the source position of the declaration of an object name. -// The result may be an invalid position if it cannot be computed -// (obj.Decl may be nil or not correct). -func (obj *Object) Pos() token.Pos { - name := obj.Name - switch d := obj.Decl.(type) { - case *Field: - for _, n := range d.Names { - if n.Name == name { - return n.Pos() - } - } - case *ImportSpec: - if d.Name != nil && d.Name.Name == name { - return d.Name.Pos() - } - return d.Path.Pos() - case *ValueSpec: - for _, n := range d.Names { - if n.Name == name { - return n.Pos() - } - } - case *TypeSpec: - if d.Name.Name == name { - return d.Name.Pos() - } - case *FuncDecl: - if d.Name.Name == name { - return d.Name.Pos() - } - case *LabeledStmt: - if d.Label.Name == name { - return d.Label.Pos() - } - case *AssignStmt: - for _, x := range d.Lhs { - if ident, isIdent := x.(*Ident); isIdent && ident.Name == name { - return ident.Pos() - } - } - case *Scope: - // predeclared object - nothing to do for now - } - return token.NoPos -} - -// ObjKind describes what an object represents. -type ObjKind int - -// The list of possible Object kinds. -const ( - Bad ObjKind = iota // for error handling - Pkg // package - Con // constant - Typ // type - Var // variable - Fun // function or method - Lbl // label -) - -var objKindStrings = [...]string{ - Bad: "bad", - Pkg: "package", - Con: "const", - Typ: "type", - Var: "var", - Fun: "func", - Lbl: "label", -} - -func (kind ObjKind) String() string { return objKindStrings[kind] } |