case "line":
		in.line()
	case "undef":
		in.undef()
	default:
		in.Error("unexpected token after '#':", in.Stack.Text())
	}
	return true
}

// macroName returns the name for the macro being referenced.
func (in *Input) macroName() string {
	// We use the Stack's input method; no macro processing at this stage.
	tok := in.Stack.Next()
	if tok != scanner.Ident {