// Signature = Parameters [ Result ] .
// Result = Type | Parameters .
//
func (p *parser) parseSignature(recv *types.Var) *types.Signature {
params, isVariadic := p.parseParameters()
// optional result type
var results []*types.Var
if p.tok == '(' {
var variadic bool
results, variadic = p.parseParameters()
if variadic {
p.error("... not permitted on result type")
}
}
return types.NewSignature(nil, recv, types.NewTuple(params...), types.NewTuple(results...), isVariadic)
}
func (p *importer) tuple() *types.Tuple {
vars := make([]*types.Var, p.int())
for i := range vars {
vars[i] = p.param()
}
return types.NewTuple(vars...)
}
// ResultList = Type | ParamList .
func (p *parser) parseResultList(pkg *types.Package) *types.Tuple {
switch p.tok {
case '<':
return types.NewTuple(types.NewParam(token.NoPos, pkg, "", p.parseType(pkg)))
case '(':
params, _ := p.parseParamList(pkg)
return params
default:
return nil
}
}
// ParamList = "(" [ { Parameter "," } Parameter ] ")" .
func (p *parser) parseParamList(pkg *types.Package) (*types.Tuple, bool) {
var list []*types.Var
isVariadic := false
p.expect('(')
for p.tok != ')' && p.tok != scanner.EOF {
if len(list) > 0 {
p.expect(',')
}
par, variadic := p.parseParam(pkg)
list = append(list, par)
if variadic {
if isVariadic {
p.error("... not on final argument")
}
isVariadic = true
}
}
p.expect(')')
return types.NewTuple(list...), isVariadic
}
