2 * The contents of this file are subject to the Netscape Public
3 * License Version 1.1 (the "License"); you may not use this file
4 * except in compliance with the License. You may obtain a copy of
5 * the License at http://www.mozilla.org/NPL/
7 * Software distributed under the License is distributed on an
8 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either expressed
9 * or implied. See the License for the specific language governing
10 * rights and limitations under the License.
12 * The Original Code is mozilla.org code.
14 * The Initial Developer of the Original Code is Netscape
15 * Communications Corporation. Portions created by Netscape are
16 * Copyright (C) 1998 Netscape Communications Corporation.
17 * All Rights Reserved.
19 * Contributor(s): pschwartau@netscape.com
22 * SUMMARY: Applying Function.prototype.call to the Function object itself
25 * ECMA-262 15.3.4.4 Function.prototype.call (thisArg [,arg1 [,arg2,
\85] ] )
27 * When applied to the Function object itself, thisArg should be ignored.
28 * As explained by Waldemar (waldemar@netscape.com):
30 * Function.call(obj, "print(this)") is equivalent to invoking
31 * Function("print(this)") with this set to obj. Now, Function("print(this)")
32 * is equivalent to new Function("print(this)") (see 15.3.1.1), and the latter
33 * ignores the this value that you passed it and constructs a function
34 * (which we'll call F) which will print the value of the this that will be
35 * passed in when F will be invoked.
37 * With the last set of () you're invoking F(), which means you're calling it
38 * with no this value. When you don't provide a this value, it defaults to the
42 //-----------------------------------------------------------------------------
45 var summary = 'Applying Function.prototype.call to the Function object itself';
49 var actualvalues = [];
51 var expectedvalues = [];
52 var self = this; // capture a reference to the global object
53 var cnOBJECT_GLOBAL = self.toString();
54 var cnOBJECT_OBJECT = (new Object).toString();
55 var cnHello = 'Hello';
57 var objTEST = {color:cnRed};
58 var f = new Function();
59 var g = new Function();
62 f = Function.call(self, 'return cnHello');
63 g = Function.call(objTEST, 'return cnHello');
65 status = 'Section A of test';
70 status = 'Section B of test';
76 f = Function.call(self, 'return this.toString()');
77 g = Function.call(objTEST, 'return this.toString()');
79 status = 'Section C of test';
81 expect = cnOBJECT_GLOBAL;
84 status = 'Section D of test';
86 expect = cnOBJECT_GLOBAL;
90 f = Function.call(self, 'return this.color');
91 g = Function.call(objTEST, 'return this.color');
93 status = 'Section E of test';
98 status = 'Section F of test';
105 //-----------------------------------------------------------------------------
107 //-----------------------------------------------------------------------------
110 function captureThis()
112 statusitems[UBound] = status;
113 actualvalues[UBound] = actual;
114 expectedvalues[UBound] = expect;
122 printBugNumber (bug);
123 printStatus (summary);
125 for (var i = 0; i < UBound; i++)
127 reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);