to_str

/* :nodoc: */
static VALUE
name_err_mesg_to_str(obj)
    VALUE obj;
{
    VALUE *ptr, mesg;
    Data_Get_Struct(obj, VALUE, ptr);

    mesg = ptr[0];
    if (NIL_P(mesg)) return Qnil;
    else {
        const char *desc = 0;
        VALUE d = 0, args[3];

        obj = ptr[1];
        switch (TYPE(obj)) {
          case T_NIL:
            desc = "nil";
            break;
          case T_TRUE:
            desc = "true";
            break;
          case T_FALSE:
            desc = "false";
            break;
          default:
            d = rb_protect(rb_inspect, obj, 0);
            if (NIL_P(d) || RSTRING(d)->len > 65) {
                d = rb_any_to_s(obj);
            }
            desc = RSTRING(d)->ptr;
            break;
        }
        if (desc && desc[0] != '#') {
            d = rb_str_new2(desc);
            rb_str_cat2(d, ":");
            rb_str_cat2(d, rb_obj_classname(obj));
        }
        args[0] = mesg;
        args[1] = ptr[2];
        args[2] = d;
        mesg = rb_f_sprintf(3, args);
    }
    if (OBJ_TAINTED(obj)) OBJ_TAINT(mesg);
    return mesg;
}