func init() {
scope = ast.NewScope(nil)
Universe = scope
Bool = defType("bool")
defType("byte") // TODO(gri) should be an alias for uint8
defType("complex64")
Complex128 = defType("complex128")
defType("float32")
Float64 = defType("float64")
defType("int8")
defType("int16")
defType("int32")
defType("int64")
String = defType("string")
defType("uint8")
defType("uint16")
defType("uint32")
defType("uint64")
Int = defType("int")
defType("uint")
defType("uintptr")
defConst("true")
defConst("false")
defConst("iota")
defConst("nil")
defFun("append")
defFun("cap")
defFun("close")
defFun("complex")
defFun("copy")
defFun("imag")
defFun("len")
defFun("make")
defFun("new")
defFun("panic")
defFun("print")
defFun("println")
defFun("real")
defFun("recover")
scope = ast.NewScope(nil)
Unsafe = ast.NewObj(ast.Pkg, "unsafe")
Unsafe.Data = scope
defType("Pointer")
defFun("Alignof")
defFun("New")
defFun("NewArray")
defFun("Offsetof")
defFun("Reflect")
defFun("Sizeof")
defFun("Typeof")
defFun("Unreflect")
}
// Export = "PackageClause { Decl } "$$" .
// PackageClause = "package" identifier [ "safe" ] "\n" .
//
func (p *gcParser) parseExport() *ast.Object {
p.expectKeyword("package")
name := p.expect(scanner.Ident)
if p.tok != '\n' {
// A package is safe if it was compiled with the -u flag,
// which disables the unsafe package.
// TODO(gri) remember "safe" package
p.expectKeyword("safe")
}
p.expect('\n')
assert(p.imports[p.id] == nil)
pkg := ast.NewObj(ast.Pkg, name)
pkg.Data = ast.NewScope(nil)
p.imports[p.id] = pkg
for p.tok != '$' && p.tok != scanner.EOF {
p.parseDecl()
}
if ch := p.scanner.Peek(); p.tok != '$' || ch != '$' {
// don't call next()/expect() since reading past the
// export data may cause scanner errors (e.g. NUL chars)
p.errorf("expected '$$', got %s %c", scanner.TokenString(p.tok), ch)
}
if n := p.scanner.ErrorCount; n != 0 {
p.errorf("expected no scanner errors, got %d", n)
}
return pkg
}
// ImportPath = string_lit .
//
func (p *gcParser) parsePkgId() *ast.Object {
id, err := strconv.Unquote(p.expect(scanner.String))
if err != nil {
p.error(err)
}
switch id {
case "":
// id == "" stands for the imported package id
// (only known at time of package installation)
id = p.id
case "unsafe":
// package unsafe is not in the imports map - handle explicitly
return Unsafe
}
pkg := p.imports[id]
if pkg == nil {
scope = ast.NewScope(nil)
pkg = ast.NewObj(ast.Pkg, "")
pkg.Data = scope
p.imports[id] = pkg
}
return pkg
}
func (tc *typechecker) declSignature(typ *Type, recv, params, results *ast.FieldList) {
assert((typ.Form == Method) == (recv != nil))
typ.Params = ast.NewScope(nil)
tc.declFields(typ.Params, recv, true)
tc.declFields(typ.Params, params, true)
typ.N = tc.declFields(typ.Params, results, true)
}
func (tc *typechecker) bindMethod(method *ast.FuncDecl) {
// a method is declared in the receiver base type's scope
var scope *ast.Scope
base := deref(method.Recv.List[0].Type)
if name, isIdent := base.(*ast.Ident); isIdent {
// if base is not an *ast.Ident, we had a syntax
// error and the parser reported an error already
obj := tc.topScope.Lookup(name.Name)
if obj == nil {
tc.Errorf(name.Pos(), "invalid receiver: %s is not declared in this package", name.Name)
} else if obj.Kind != ast.Typ {
tc.Errorf(name.Pos(), "invalid receiver: %s is not a type", name.Name)
} else {
typ := obj.Type.(*Type)
assert(typ.Form == Unresolved)
scope = typ.Scope
}
}
if scope == nil {
// no receiver type found; use a dummy scope
// (we still want to type-check the method
// body, so make sure there is a name object
// and type)
// TODO(gri) should we record the scope so
// that we don't lose the receiver for type-
// checking of the method body?
scope = ast.NewScope(nil)
}
tc.declInScope(scope, ast.Fun, method.Name, method, 0)
}
func init() {
Universe = ast.NewScope(nil)
// basic types
for n, name := range BasicTypes {
typ := NewType(Basic)
typ.N = n
obj := ast.NewObj(ast.Typ, name)
obj.Type = typ
typ.Obj = obj
def(obj)
}
// built-in functions
// TODO(gri) implement this
}
// NewType creates a new type of a given form.
func NewType(form Form) *Type {
return &Type{Form: form, Scope: ast.NewScope(nil)}
}
func (tc *typechecker) openScope() *ast.Scope {
tc.topScope = ast.NewScope(tc.topScope)
return tc.topScope
}
