/*
 *   call-seq:
 *      Debugger.checkpoint = string -> string
 *
 *   Sets checkpoint.
 */
static VALUE
debug_set_catchpoint(VALUE self, VALUE value)
{
    debug_check_started();

    if (!NIL_P(value) && TYPE(value) != T_STRING) {
        rb_raise(rb_eTypeError, "value of checkpoint must be String");
    }
    if(NIL_P(value))
    catchpoint = Qnil;
    else
    catchpoint = rb_str_dup(value);
    return value;
}