// Copyright (C) 2015 André Bargull. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
info: Operator --x evaluates its reference expression once.
description: >
    The operand expression is evaluated exactly once. Operand expression is
    MemberExpression: base[prop]. ToPropertyKey(prop) is not called multiple
    times.
---*/

var propKeyEvaluated = false;
var base = {};
var prop = {
  toString: function() {
    assert(!propKeyEvaluated);
    propKeyEvaluated = true;
    return 1;
  }
};

--base[prop];