func isName(n ast.Expr, name string) bool {
	id, ok := n.(*ast.Ident)
	return ok && id.String() == name
}
func isName(n ast.Expr, name string) bool {
	id, ok := n.(*ast.Ident)
	return ok && id.String() == name
}
// isName returns true if n is an identifier with the given name.