gecko/toolkit/components/url-classifier/content/moz/lang.js

# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is Google Safe Browsing.
#
# The Initial Developer of the Original Code is Google Inc.
# Portions created by the Initial Developer are Copyright (C) 2006
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
#   Aaron Boodman <aa@google.com> (original author)
#
# Alternatively, the contents of this file may be used under the terms of
# either the GNU General Public License Version 2 or later (the "GPL"), or
# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
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# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
#
# ***** END LICENSE BLOCK *****


/**
 * lang.js - Some missing JavaScript language features
 */

/**
 * Partially applies this function to a particular "this object" and zero or
 * more arguments. The result is a new function with some arguments of the first
 * function pre-filled and the value of |this| "pre-specified".
 *
 * Remaining arguments specified at call-time are appended to the pre-
 * specified ones.
 *
 * Usage:
 * var barMethBound = bind(myFunction, myObj, "arg1", "arg2");
 * barMethBound("arg3", "arg4");
 *
 * @param thisObj {object} Specifies the object which |this| should point to
 * when the function is run. If the value is null or undefined, it will default
 * to the global object.
 *
 * @returns {function} A partially-applied form of the function bind() was
 * invoked as a method of.
 */
function bind(fn, self, opt_args) {
  var boundargs = (typeof fn.boundArgs_ != "undefined") ? fn.boundArgs_ : [];
  boundargs = boundargs.concat(Array.prototype.slice.call(arguments, 2));

  if (typeof fn.boundSelf_ != "undefined") {
    self = fn.boundSelf_;
  }

  if (typeof fn.boundFn_ != "undefined") {
    fn = fn.boundFn_;
  }

  var newfn = function() {
    // Combine the static args and the new args into one big array
    var args = boundargs.concat(Array.prototype.slice.call(arguments));
    return fn.apply(self, args);
  }

  newfn.boundArgs_ = boundargs;
  newfn.boundSelf_ = self;
  newfn.boundFn_ = fn;

  return newfn;
}

/**
 * An alias to the bind() global function.
 *
 * Usage:
 * var g = f.bind(obj, arg1, arg2);
 * g(arg3, arg4);
 */
Function.prototype.bind = function(self, opt_args) {
  return bind.apply(
    null, [this, self].concat(Array.prototype.slice.call(arguments, 1)));
}

/**
 * Unbelievably, Function inheritence is broken in chrome in Firefox
 * (still as of FFox 1.5b1). Hence if you're working in an extension
 * and not using the subscriptloader, you can't use the method
 * above. Instead, use this global function that does roughly the same
 * thing.
 *
 * //XXX is this still the case?
 *
 ***************************************************************************
 *   NOTE THE REVERSED ORDER OF FUNCTION AND OBJECT REFERENCES AS bind()   *
 ***************************************************************************
 * 
 * // Example to bind foo.bar():
 * var bound = BindToObject(bar, foo, "arg1", "arg2");
 * bound("arg3", "arg4");
 * 
 * @param func {string} Reference to the function to be bound
 *
 * @param obj {object} Specifies the object which |this| should point to
 * when the function is run. If the value is null or undefined, it will default
 * to the global object.
 *
 * @param opt_{...} Dummy optional arguments to make a jscompiler happy
 *
 * @returns {function} A partially-applied form of the speficied function.
 */
function BindToObject(func, obj, opt_A, opt_B, opt_C, opt_D, opt_E, opt_F) {
  // This is the sick product of Aaron's mind. Not for the feint of heart.
  var args = Array.prototype.splice.call(arguments, 1, arguments.length);
  return Function.prototype.bind.apply(func, args);
}

/**
 * Inherit the prototype methods from one constructor into another.
 *
 * Usage:
 *
 * function ParentClass(a, b) { }
 * ParentClass.prototype.foo = function(a) { }
 *
 * function ChildClass(a, b, c) {
 *   ParentClass.call(this, a, b);
 * }
 *
 * ChildClass.inherits(ParentClass);
 *
 * var child = new ChildClass("a", "b", "see");
 * child.foo(); // works
 *
 * In addition, a superclass' implementation of a method can be invoked
 * as follows:
 *
 * ChildClass.prototype.foo = function(a) {
 *   ChildClass.superClass_.foo.call(this, a);
 *   // other code
 * };
 */
Function.prototype.inherits = function(parentCtor) {
  var tempCtor = function(){};
  tempCtor.prototype = parentCtor.prototype;
  this.superClass_ = parentCtor.prototype;
  this.prototype = new tempCtor();
}