builtins/GlobalObject.js

   1 /*
   2  * Copyright (C) 2015 Yusuke Suzuki <utatane.tea@gmail.com>.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 function toInteger(target)
  27 {
  28     "use strict";
  29
  30     var numberValue = @Number(target);
  31
  32     // isNaN(numberValue)
  33     if (numberValue !== numberValue)
  34         return 0;
  35
  36     if (numberValue === 0 || !@isFinite(numberValue))
  37         return numberValue;
  38
  39     return (numberValue > 0 ? 1 : -1) * @floor(@abs(numberValue));
  40 }
  41
  42 function toLength(target)
  43 {
  44     "use strict";
  45
  46     var maxSafeInteger = 0x1FFFFFFFFFFFFF;
  47     var length = @toInteger(target);
  48     // originally Math.min(Math.max(length, 0), maxSafeInteger));
  49     return length > 0 ? (length < maxSafeInteger ? length : maxSafeInteger) : 0;
  50 }
  51
  52 function isObject(object)
  53 {
  54     "use strict";
  55
  56     return (object !== null && typeof object === "object") || typeof object === "function";
  57 }