func (p *parser) expect(tok token.Token) token.Pos {
pos := p.pos
if p.tok != tok {
p.errorExpected(pos, "'"+tok.String()+"'")
}
p.next() // make progress
return pos
}
func (p *parser) parseGenDecl(keyword token.Token, f parseSpecFunction) *ast.GenDecl {
if p.trace {
defer un(trace(p, "GenDecl("+keyword.String()+")"))
}
doc := p.leadComment
pos := p.expect(keyword)
var lparen, rparen token.Pos
var list []ast.Spec
if p.tok == token.LPAREN {
lparen = p.pos
p.next()
for p.tok != token.RPAREN && p.tok != token.EOF {
list = append(list, f(p, p.leadComment))
}
rparen = p.expect(token.RPAREN)
p.expectSemi()
} else {
list = append(list, f(p, nil))
}
return &ast.GenDecl{doc, pos, keyword, lparen, list, rparen}
}