inspect

static VALUE
rb_ast_node_inspect(VALUE self)
{
    VALUE str;
    VALUE cname;
    struct ASTNodeData *data;
    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);

    cname = rb_class_path(rb_obj_class(self));
    str = rb_str_new2("#<");

    rb_str_append(str, cname);
    rb_str_catf(str, ":%s@%d:%d-%d:%d>",
                node_type_to_str(data->node),
                nd_first_lineno(data->node), nd_first_column(data->node),
                nd_last_lineno(data->node), nd_last_column(data->node));

    return str;
}