github.com/mmatczuk/gohan@v0.0.0-20170206152520-30e45d9bdb69/examples/npm_example/node_modules/underscore/underscore.js (about)

     1  //     Underscore.js 1.6.0
     2  //     http://underscorejs.org
     3  //     (c) 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
     4  //     Underscore may be freely distributed under the MIT license.
     5  
     6  (function() {
     7  
     8    // Baseline setup
     9    // --------------
    10  
    11    // Establish the root object, `window` in the browser, or `exports` on the server.
    12    var root = this;
    13  
    14    // Save the previous value of the `_` variable.
    15    var previousUnderscore = root._;
    16  
    17    // Establish the object that gets returned to break out of a loop iteration.
    18    var breaker = {};
    19  
    20    // Save bytes in the minified (but not gzipped) version:
    21    var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype;
    22  
    23    // Create quick reference variables for speed access to core prototypes.
    24    var
    25      push             = ArrayProto.push,
    26      slice            = ArrayProto.slice,
    27      concat           = ArrayProto.concat,
    28      toString         = ObjProto.toString,
    29      hasOwnProperty   = ObjProto.hasOwnProperty;
    30  
    31    // All **ECMAScript 5** native function implementations that we hope to use
    32    // are declared here.
    33    var
    34      nativeForEach      = ArrayProto.forEach,
    35      nativeMap          = ArrayProto.map,
    36      nativeReduce       = ArrayProto.reduce,
    37      nativeReduceRight  = ArrayProto.reduceRight,
    38      nativeFilter       = ArrayProto.filter,
    39      nativeEvery        = ArrayProto.every,
    40      nativeSome         = ArrayProto.some,
    41      nativeIndexOf      = ArrayProto.indexOf,
    42      nativeLastIndexOf  = ArrayProto.lastIndexOf,
    43      nativeIsArray      = Array.isArray,
    44      nativeKeys         = Object.keys,
    45      nativeBind         = FuncProto.bind;
    46  
    47    // Create a safe reference to the Underscore object for use below.
    48    var _ = function(obj) {
    49      if (obj instanceof _) return obj;
    50      if (!(this instanceof _)) return new _(obj);
    51      this._wrapped = obj;
    52    };
    53  
    54    // Export the Underscore object for **Node.js**, with
    55    // backwards-compatibility for the old `require()` API. If we're in
    56    // the browser, add `_` as a global object via a string identifier,
    57    // for Closure Compiler "advanced" mode.
    58    if (typeof exports !== 'undefined') {
    59      if (typeof module !== 'undefined' && module.exports) {
    60        exports = module.exports = _;
    61      }
    62      exports._ = _;
    63    } else {
    64      root._ = _;
    65    }
    66  
    67    // Current version.
    68    _.VERSION = '1.6.0';
    69  
    70    // Collection Functions
    71    // --------------------
    72  
    73    // The cornerstone, an `each` implementation, aka `forEach`.
    74    // Handles objects with the built-in `forEach`, arrays, and raw objects.
    75    // Delegates to **ECMAScript 5**'s native `forEach` if available.
    76    var each = _.each = _.forEach = function(obj, iterator, context) {
    77      if (obj == null) return obj;
    78      if (nativeForEach && obj.forEach === nativeForEach) {
    79        obj.forEach(iterator, context);
    80      } else if (obj.length === +obj.length) {
    81        for (var i = 0, length = obj.length; i < length; i++) {
    82          if (iterator.call(context, obj[i], i, obj) === breaker) return;
    83        }
    84      } else {
    85        var keys = _.keys(obj);
    86        for (var i = 0, length = keys.length; i < length; i++) {
    87          if (iterator.call(context, obj[keys[i]], keys[i], obj) === breaker) return;
    88        }
    89      }
    90      return obj;
    91    };
    92  
    93    // Return the results of applying the iterator to each element.
    94    // Delegates to **ECMAScript 5**'s native `map` if available.
    95    _.map = _.collect = function(obj, iterator, context) {
    96      var results = [];
    97      if (obj == null) return results;
    98      if (nativeMap && obj.map === nativeMap) return obj.map(iterator, context);
    99      each(obj, function(value, index, list) {
   100        results.push(iterator.call(context, value, index, list));
   101      });
   102      return results;
   103    };
   104  
   105    var reduceError = 'Reduce of empty array with no initial value';
   106  
   107    // **Reduce** builds up a single result from a list of values, aka `inject`,
   108    // or `foldl`. Delegates to **ECMAScript 5**'s native `reduce` if available.
   109    _.reduce = _.foldl = _.inject = function(obj, iterator, memo, context) {
   110      var initial = arguments.length > 2;
   111      if (obj == null) obj = [];
   112      if (nativeReduce && obj.reduce === nativeReduce) {
   113        if (context) iterator = _.bind(iterator, context);
   114        return initial ? obj.reduce(iterator, memo) : obj.reduce(iterator);
   115      }
   116      each(obj, function(value, index, list) {
   117        if (!initial) {
   118          memo = value;
   119          initial = true;
   120        } else {
   121          memo = iterator.call(context, memo, value, index, list);
   122        }
   123      });
   124      if (!initial) throw new TypeError(reduceError);
   125      return memo;
   126    };
   127  
   128    // The right-associative version of reduce, also known as `foldr`.
   129    // Delegates to **ECMAScript 5**'s native `reduceRight` if available.
   130    _.reduceRight = _.foldr = function(obj, iterator, memo, context) {
   131      var initial = arguments.length > 2;
   132      if (obj == null) obj = [];
   133      if (nativeReduceRight && obj.reduceRight === nativeReduceRight) {
   134        if (context) iterator = _.bind(iterator, context);
   135        return initial ? obj.reduceRight(iterator, memo) : obj.reduceRight(iterator);
   136      }
   137      var length = obj.length;
   138      if (length !== +length) {
   139        var keys = _.keys(obj);
   140        length = keys.length;
   141      }
   142      each(obj, function(value, index, list) {
   143        index = keys ? keys[--length] : --length;
   144        if (!initial) {
   145          memo = obj[index];
   146          initial = true;
   147        } else {
   148          memo = iterator.call(context, memo, obj[index], index, list);
   149        }
   150      });
   151      if (!initial) throw new TypeError(reduceError);
   152      return memo;
   153    };
   154  
   155    // Return the first value which passes a truth test. Aliased as `detect`.
   156    _.find = _.detect = function(obj, predicate, context) {
   157      var result;
   158      any(obj, function(value, index, list) {
   159        if (predicate.call(context, value, index, list)) {
   160          result = value;
   161          return true;
   162        }
   163      });
   164      return result;
   165    };
   166  
   167    // Return all the elements that pass a truth test.
   168    // Delegates to **ECMAScript 5**'s native `filter` if available.
   169    // Aliased as `select`.
   170    _.filter = _.select = function(obj, predicate, context) {
   171      var results = [];
   172      if (obj == null) return results;
   173      if (nativeFilter && obj.filter === nativeFilter) return obj.filter(predicate, context);
   174      each(obj, function(value, index, list) {
   175        if (predicate.call(context, value, index, list)) results.push(value);
   176      });
   177      return results;
   178    };
   179  
   180    // Return all the elements for which a truth test fails.
   181    _.reject = function(obj, predicate, context) {
   182      return _.filter(obj, function(value, index, list) {
   183        return !predicate.call(context, value, index, list);
   184      }, context);
   185    };
   186  
   187    // Determine whether all of the elements match a truth test.
   188    // Delegates to **ECMAScript 5**'s native `every` if available.
   189    // Aliased as `all`.
   190    _.every = _.all = function(obj, predicate, context) {
   191      predicate || (predicate = _.identity);
   192      var result = true;
   193      if (obj == null) return result;
   194      if (nativeEvery && obj.every === nativeEvery) return obj.every(predicate, context);
   195      each(obj, function(value, index, list) {
   196        if (!(result = result && predicate.call(context, value, index, list))) return breaker;
   197      });
   198      return !!result;
   199    };
   200  
   201    // Determine if at least one element in the object matches a truth test.
   202    // Delegates to **ECMAScript 5**'s native `some` if available.
   203    // Aliased as `any`.
   204    var any = _.some = _.any = function(obj, predicate, context) {
   205      predicate || (predicate = _.identity);
   206      var result = false;
   207      if (obj == null) return result;
   208      if (nativeSome && obj.some === nativeSome) return obj.some(predicate, context);
   209      each(obj, function(value, index, list) {
   210        if (result || (result = predicate.call(context, value, index, list))) return breaker;
   211      });
   212      return !!result;
   213    };
   214  
   215    // Determine if the array or object contains a given value (using `===`).
   216    // Aliased as `include`.
   217    _.contains = _.include = function(obj, target) {
   218      if (obj == null) return false;
   219      if (nativeIndexOf && obj.indexOf === nativeIndexOf) return obj.indexOf(target) != -1;
   220      return any(obj, function(value) {
   221        return value === target;
   222      });
   223    };
   224  
   225    // Invoke a method (with arguments) on every item in a collection.
   226    _.invoke = function(obj, method) {
   227      var args = slice.call(arguments, 2);
   228      var isFunc = _.isFunction(method);
   229      return _.map(obj, function(value) {
   230        return (isFunc ? method : value[method]).apply(value, args);
   231      });
   232    };
   233  
   234    // Convenience version of a common use case of `map`: fetching a property.
   235    _.pluck = function(obj, key) {
   236      return _.map(obj, _.property(key));
   237    };
   238  
   239    // Convenience version of a common use case of `filter`: selecting only objects
   240    // containing specific `key:value` pairs.
   241    _.where = function(obj, attrs) {
   242      return _.filter(obj, _.matches(attrs));
   243    };
   244  
   245    // Convenience version of a common use case of `find`: getting the first object
   246    // containing specific `key:value` pairs.
   247    _.findWhere = function(obj, attrs) {
   248      return _.find(obj, _.matches(attrs));
   249    };
   250  
   251    // Return the maximum element or (element-based computation).
   252    // Can't optimize arrays of integers longer than 65,535 elements.
   253    // See [WebKit Bug 80797](https://bugs.webkit.org/show_bug.cgi?id=80797)
   254    _.max = function(obj, iterator, context) {
   255      if (!iterator && _.isArray(obj) && obj[0] === +obj[0] && obj.length < 65535) {
   256        return Math.max.apply(Math, obj);
   257      }
   258      var result = -Infinity, lastComputed = -Infinity;
   259      each(obj, function(value, index, list) {
   260        var computed = iterator ? iterator.call(context, value, index, list) : value;
   261        if (computed > lastComputed) {
   262          result = value;
   263          lastComputed = computed;
   264        }
   265      });
   266      return result;
   267    };
   268  
   269    // Return the minimum element (or element-based computation).
   270    _.min = function(obj, iterator, context) {
   271      if (!iterator && _.isArray(obj) && obj[0] === +obj[0] && obj.length < 65535) {
   272        return Math.min.apply(Math, obj);
   273      }
   274      var result = Infinity, lastComputed = Infinity;
   275      each(obj, function(value, index, list) {
   276        var computed = iterator ? iterator.call(context, value, index, list) : value;
   277        if (computed < lastComputed) {
   278          result = value;
   279          lastComputed = computed;
   280        }
   281      });
   282      return result;
   283    };
   284  
   285    // Shuffle an array, using the modern version of the
   286    // [Fisher-Yates shuffle](http://en.wikipedia.org/wiki/Fisher–Yates_shuffle).
   287    _.shuffle = function(obj) {
   288      var rand;
   289      var index = 0;
   290      var shuffled = [];
   291      each(obj, function(value) {
   292        rand = _.random(index++);
   293        shuffled[index - 1] = shuffled[rand];
   294        shuffled[rand] = value;
   295      });
   296      return shuffled;
   297    };
   298  
   299    // Sample **n** random values from a collection.
   300    // If **n** is not specified, returns a single random element.
   301    // The internal `guard` argument allows it to work with `map`.
   302    _.sample = function(obj, n, guard) {
   303      if (n == null || guard) {
   304        if (obj.length !== +obj.length) obj = _.values(obj);
   305        return obj[_.random(obj.length - 1)];
   306      }
   307      return _.shuffle(obj).slice(0, Math.max(0, n));
   308    };
   309  
   310    // An internal function to generate lookup iterators.
   311    var lookupIterator = function(value) {
   312      if (value == null) return _.identity;
   313      if (_.isFunction(value)) return value;
   314      return _.property(value);
   315    };
   316  
   317    // Sort the object's values by a criterion produced by an iterator.
   318    _.sortBy = function(obj, iterator, context) {
   319      iterator = lookupIterator(iterator);
   320      return _.pluck(_.map(obj, function(value, index, list) {
   321        return {
   322          value: value,
   323          index: index,
   324          criteria: iterator.call(context, value, index, list)
   325        };
   326      }).sort(function(left, right) {
   327        var a = left.criteria;
   328        var b = right.criteria;
   329        if (a !== b) {
   330          if (a > b || a === void 0) return 1;
   331          if (a < b || b === void 0) return -1;
   332        }
   333        return left.index - right.index;
   334      }), 'value');
   335    };
   336  
   337    // An internal function used for aggregate "group by" operations.
   338    var group = function(behavior) {
   339      return function(obj, iterator, context) {
   340        var result = {};
   341        iterator = lookupIterator(iterator);
   342        each(obj, function(value, index) {
   343          var key = iterator.call(context, value, index, obj);
   344          behavior(result, key, value);
   345        });
   346        return result;
   347      };
   348    };
   349  
   350    // Groups the object's values by a criterion. Pass either a string attribute
   351    // to group by, or a function that returns the criterion.
   352    _.groupBy = group(function(result, key, value) {
   353      _.has(result, key) ? result[key].push(value) : result[key] = [value];
   354    });
   355  
   356    // Indexes the object's values by a criterion, similar to `groupBy`, but for
   357    // when you know that your index values will be unique.
   358    _.indexBy = group(function(result, key, value) {
   359      result[key] = value;
   360    });
   361  
   362    // Counts instances of an object that group by a certain criterion. Pass
   363    // either a string attribute to count by, or a function that returns the
   364    // criterion.
   365    _.countBy = group(function(result, key) {
   366      _.has(result, key) ? result[key]++ : result[key] = 1;
   367    });
   368  
   369    // Use a comparator function to figure out the smallest index at which
   370    // an object should be inserted so as to maintain order. Uses binary search.
   371    _.sortedIndex = function(array, obj, iterator, context) {
   372      iterator = lookupIterator(iterator);
   373      var value = iterator.call(context, obj);
   374      var low = 0, high = array.length;
   375      while (low < high) {
   376        var mid = (low + high) >>> 1;
   377        iterator.call(context, array[mid]) < value ? low = mid + 1 : high = mid;
   378      }
   379      return low;
   380    };
   381  
   382    // Safely create a real, live array from anything iterable.
   383    _.toArray = function(obj) {
   384      if (!obj) return [];
   385      if (_.isArray(obj)) return slice.call(obj);
   386      if (obj.length === +obj.length) return _.map(obj, _.identity);
   387      return _.values(obj);
   388    };
   389  
   390    // Return the number of elements in an object.
   391    _.size = function(obj) {
   392      if (obj == null) return 0;
   393      return (obj.length === +obj.length) ? obj.length : _.keys(obj).length;
   394    };
   395  
   396    // Array Functions
   397    // ---------------
   398  
   399    // Get the first element of an array. Passing **n** will return the first N
   400    // values in the array. Aliased as `head` and `take`. The **guard** check
   401    // allows it to work with `_.map`.
   402    _.first = _.head = _.take = function(array, n, guard) {
   403      if (array == null) return void 0;
   404      if ((n == null) || guard) return array[0];
   405      if (n < 0) return [];
   406      return slice.call(array, 0, n);
   407    };
   408  
   409    // Returns everything but the last entry of the array. Especially useful on
   410    // the arguments object. Passing **n** will return all the values in
   411    // the array, excluding the last N. The **guard** check allows it to work with
   412    // `_.map`.
   413    _.initial = function(array, n, guard) {
   414      return slice.call(array, 0, array.length - ((n == null) || guard ? 1 : n));
   415    };
   416  
   417    // Get the last element of an array. Passing **n** will return the last N
   418    // values in the array. The **guard** check allows it to work with `_.map`.
   419    _.last = function(array, n, guard) {
   420      if (array == null) return void 0;
   421      if ((n == null) || guard) return array[array.length - 1];
   422      return slice.call(array, Math.max(array.length - n, 0));
   423    };
   424  
   425    // Returns everything but the first entry of the array. Aliased as `tail` and `drop`.
   426    // Especially useful on the arguments object. Passing an **n** will return
   427    // the rest N values in the array. The **guard**
   428    // check allows it to work with `_.map`.
   429    _.rest = _.tail = _.drop = function(array, n, guard) {
   430      return slice.call(array, (n == null) || guard ? 1 : n);
   431    };
   432  
   433    // Trim out all falsy values from an array.
   434    _.compact = function(array) {
   435      return _.filter(array, _.identity);
   436    };
   437  
   438    // Internal implementation of a recursive `flatten` function.
   439    var flatten = function(input, shallow, output) {
   440      if (shallow && _.every(input, _.isArray)) {
   441        return concat.apply(output, input);
   442      }
   443      each(input, function(value) {
   444        if (_.isArray(value) || _.isArguments(value)) {
   445          shallow ? push.apply(output, value) : flatten(value, shallow, output);
   446        } else {
   447          output.push(value);
   448        }
   449      });
   450      return output;
   451    };
   452  
   453    // Flatten out an array, either recursively (by default), or just one level.
   454    _.flatten = function(array, shallow) {
   455      return flatten(array, shallow, []);
   456    };
   457  
   458    // Return a version of the array that does not contain the specified value(s).
   459    _.without = function(array) {
   460      return _.difference(array, slice.call(arguments, 1));
   461    };
   462  
   463    // Split an array into two arrays: one whose elements all satisfy the given
   464    // predicate, and one whose elements all do not satisfy the predicate.
   465    _.partition = function(array, predicate) {
   466      var pass = [], fail = [];
   467      each(array, function(elem) {
   468        (predicate(elem) ? pass : fail).push(elem);
   469      });
   470      return [pass, fail];
   471    };
   472  
   473    // Produce a duplicate-free version of the array. If the array has already
   474    // been sorted, you have the option of using a faster algorithm.
   475    // Aliased as `unique`.
   476    _.uniq = _.unique = function(array, isSorted, iterator, context) {
   477      if (_.isFunction(isSorted)) {
   478        context = iterator;
   479        iterator = isSorted;
   480        isSorted = false;
   481      }
   482      var initial = iterator ? _.map(array, iterator, context) : array;
   483      var results = [];
   484      var seen = [];
   485      each(initial, function(value, index) {
   486        if (isSorted ? (!index || seen[seen.length - 1] !== value) : !_.contains(seen, value)) {
   487          seen.push(value);
   488          results.push(array[index]);
   489        }
   490      });
   491      return results;
   492    };
   493  
   494    // Produce an array that contains the union: each distinct element from all of
   495    // the passed-in arrays.
   496    _.union = function() {
   497      return _.uniq(_.flatten(arguments, true));
   498    };
   499  
   500    // Produce an array that contains every item shared between all the
   501    // passed-in arrays.
   502    _.intersection = function(array) {
   503      var rest = slice.call(arguments, 1);
   504      return _.filter(_.uniq(array), function(item) {
   505        return _.every(rest, function(other) {
   506          return _.contains(other, item);
   507        });
   508      });
   509    };
   510  
   511    // Take the difference between one array and a number of other arrays.
   512    // Only the elements present in just the first array will remain.
   513    _.difference = function(array) {
   514      var rest = concat.apply(ArrayProto, slice.call(arguments, 1));
   515      return _.filter(array, function(value){ return !_.contains(rest, value); });
   516    };
   517  
   518    // Zip together multiple lists into a single array -- elements that share
   519    // an index go together.
   520    _.zip = function() {
   521      var length = _.max(_.pluck(arguments, 'length').concat(0));
   522      var results = new Array(length);
   523      for (var i = 0; i < length; i++) {
   524        results[i] = _.pluck(arguments, '' + i);
   525      }
   526      return results;
   527    };
   528  
   529    // Converts lists into objects. Pass either a single array of `[key, value]`
   530    // pairs, or two parallel arrays of the same length -- one of keys, and one of
   531    // the corresponding values.
   532    _.object = function(list, values) {
   533      if (list == null) return {};
   534      var result = {};
   535      for (var i = 0, length = list.length; i < length; i++) {
   536        if (values) {
   537          result[list[i]] = values[i];
   538        } else {
   539          result[list[i][0]] = list[i][1];
   540        }
   541      }
   542      return result;
   543    };
   544  
   545    // If the browser doesn't supply us with indexOf (I'm looking at you, **MSIE**),
   546    // we need this function. Return the position of the first occurrence of an
   547    // item in an array, or -1 if the item is not included in the array.
   548    // Delegates to **ECMAScript 5**'s native `indexOf` if available.
   549    // If the array is large and already in sort order, pass `true`
   550    // for **isSorted** to use binary search.
   551    _.indexOf = function(array, item, isSorted) {
   552      if (array == null) return -1;
   553      var i = 0, length = array.length;
   554      if (isSorted) {
   555        if (typeof isSorted == 'number') {
   556          i = (isSorted < 0 ? Math.max(0, length + isSorted) : isSorted);
   557        } else {
   558          i = _.sortedIndex(array, item);
   559          return array[i] === item ? i : -1;
   560        }
   561      }
   562      if (nativeIndexOf && array.indexOf === nativeIndexOf) return array.indexOf(item, isSorted);
   563      for (; i < length; i++) if (array[i] === item) return i;
   564      return -1;
   565    };
   566  
   567    // Delegates to **ECMAScript 5**'s native `lastIndexOf` if available.
   568    _.lastIndexOf = function(array, item, from) {
   569      if (array == null) return -1;
   570      var hasIndex = from != null;
   571      if (nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf) {
   572        return hasIndex ? array.lastIndexOf(item, from) : array.lastIndexOf(item);
   573      }
   574      var i = (hasIndex ? from : array.length);
   575      while (i--) if (array[i] === item) return i;
   576      return -1;
   577    };
   578  
   579    // Generate an integer Array containing an arithmetic progression. A port of
   580    // the native Python `range()` function. See
   581    // [the Python documentation](http://docs.python.org/library/functions.html#range).
   582    _.range = function(start, stop, step) {
   583      if (arguments.length <= 1) {
   584        stop = start || 0;
   585        start = 0;
   586      }
   587      step = arguments[2] || 1;
   588  
   589      var length = Math.max(Math.ceil((stop - start) / step), 0);
   590      var idx = 0;
   591      var range = new Array(length);
   592  
   593      while(idx < length) {
   594        range[idx++] = start;
   595        start += step;
   596      }
   597  
   598      return range;
   599    };
   600  
   601    // Function (ahem) Functions
   602    // ------------------
   603  
   604    // Reusable constructor function for prototype setting.
   605    var ctor = function(){};
   606  
   607    // Create a function bound to a given object (assigning `this`, and arguments,
   608    // optionally). Delegates to **ECMAScript 5**'s native `Function.bind` if
   609    // available.
   610    _.bind = function(func, context) {
   611      var args, bound;
   612      if (nativeBind && func.bind === nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
   613      if (!_.isFunction(func)) throw new TypeError;
   614      args = slice.call(arguments, 2);
   615      return bound = function() {
   616        if (!(this instanceof bound)) return func.apply(context, args.concat(slice.call(arguments)));
   617        ctor.prototype = func.prototype;
   618        var self = new ctor;
   619        ctor.prototype = null;
   620        var result = func.apply(self, args.concat(slice.call(arguments)));
   621        if (Object(result) === result) return result;
   622        return self;
   623      };
   624    };
   625  
   626    // Partially apply a function by creating a version that has had some of its
   627    // arguments pre-filled, without changing its dynamic `this` context. _ acts
   628    // as a placeholder, allowing any combination of arguments to be pre-filled.
   629    _.partial = function(func) {
   630      var boundArgs = slice.call(arguments, 1);
   631      return function() {
   632        var position = 0;
   633        var args = boundArgs.slice();
   634        for (var i = 0, length = args.length; i < length; i++) {
   635          if (args[i] === _) args[i] = arguments[position++];
   636        }
   637        while (position < arguments.length) args.push(arguments[position++]);
   638        return func.apply(this, args);
   639      };
   640    };
   641  
   642    // Bind a number of an object's methods to that object. Remaining arguments
   643    // are the method names to be bound. Useful for ensuring that all callbacks
   644    // defined on an object belong to it.
   645    _.bindAll = function(obj) {
   646      var funcs = slice.call(arguments, 1);
   647      if (funcs.length === 0) throw new Error('bindAll must be passed function names');
   648      each(funcs, function(f) { obj[f] = _.bind(obj[f], obj); });
   649      return obj;
   650    };
   651  
   652    // Memoize an expensive function by storing its results.
   653    _.memoize = function(func, hasher) {
   654      var memo = {};
   655      hasher || (hasher = _.identity);
   656      return function() {
   657        var key = hasher.apply(this, arguments);
   658        return _.has(memo, key) ? memo[key] : (memo[key] = func.apply(this, arguments));
   659      };
   660    };
   661  
   662    // Delays a function for the given number of milliseconds, and then calls
   663    // it with the arguments supplied.
   664    _.delay = function(func, wait) {
   665      var args = slice.call(arguments, 2);
   666      return setTimeout(function(){ return func.apply(null, args); }, wait);
   667    };
   668  
   669    // Defers a function, scheduling it to run after the current call stack has
   670    // cleared.
   671    _.defer = function(func) {
   672      return _.delay.apply(_, [func, 1].concat(slice.call(arguments, 1)));
   673    };
   674  
   675    // Returns a function, that, when invoked, will only be triggered at most once
   676    // during a given window of time. Normally, the throttled function will run
   677    // as much as it can, without ever going more than once per `wait` duration;
   678    // but if you'd like to disable the execution on the leading edge, pass
   679    // `{leading: false}`. To disable execution on the trailing edge, ditto.
   680    _.throttle = function(func, wait, options) {
   681      var context, args, result;
   682      var timeout = null;
   683      var previous = 0;
   684      options || (options = {});
   685      var later = function() {
   686        previous = options.leading === false ? 0 : _.now();
   687        timeout = null;
   688        result = func.apply(context, args);
   689        context = args = null;
   690      };
   691      return function() {
   692        var now = _.now();
   693        if (!previous && options.leading === false) previous = now;
   694        var remaining = wait - (now - previous);
   695        context = this;
   696        args = arguments;
   697        if (remaining <= 0) {
   698          clearTimeout(timeout);
   699          timeout = null;
   700          previous = now;
   701          result = func.apply(context, args);
   702          context = args = null;
   703        } else if (!timeout && options.trailing !== false) {
   704          timeout = setTimeout(later, remaining);
   705        }
   706        return result;
   707      };
   708    };
   709  
   710    // Returns a function, that, as long as it continues to be invoked, will not
   711    // be triggered. The function will be called after it stops being called for
   712    // N milliseconds. If `immediate` is passed, trigger the function on the
   713    // leading edge, instead of the trailing.
   714    _.debounce = function(func, wait, immediate) {
   715      var timeout, args, context, timestamp, result;
   716  
   717      var later = function() {
   718        var last = _.now() - timestamp;
   719        if (last < wait) {
   720          timeout = setTimeout(later, wait - last);
   721        } else {
   722          timeout = null;
   723          if (!immediate) {
   724            result = func.apply(context, args);
   725            context = args = null;
   726          }
   727        }
   728      };
   729  
   730      return function() {
   731        context = this;
   732        args = arguments;
   733        timestamp = _.now();
   734        var callNow = immediate && !timeout;
   735        if (!timeout) {
   736          timeout = setTimeout(later, wait);
   737        }
   738        if (callNow) {
   739          result = func.apply(context, args);
   740          context = args = null;
   741        }
   742  
   743        return result;
   744      };
   745    };
   746  
   747    // Returns a function that will be executed at most one time, no matter how
   748    // often you call it. Useful for lazy initialization.
   749    _.once = function(func) {
   750      var ran = false, memo;
   751      return function() {
   752        if (ran) return memo;
   753        ran = true;
   754        memo = func.apply(this, arguments);
   755        func = null;
   756        return memo;
   757      };
   758    };
   759  
   760    // Returns the first function passed as an argument to the second,
   761    // allowing you to adjust arguments, run code before and after, and
   762    // conditionally execute the original function.
   763    _.wrap = function(func, wrapper) {
   764      return _.partial(wrapper, func);
   765    };
   766  
   767    // Returns a function that is the composition of a list of functions, each
   768    // consuming the return value of the function that follows.
   769    _.compose = function() {
   770      var funcs = arguments;
   771      return function() {
   772        var args = arguments;
   773        for (var i = funcs.length - 1; i >= 0; i--) {
   774          args = [funcs[i].apply(this, args)];
   775        }
   776        return args[0];
   777      };
   778    };
   779  
   780    // Returns a function that will only be executed after being called N times.
   781    _.after = function(times, func) {
   782      return function() {
   783        if (--times < 1) {
   784          return func.apply(this, arguments);
   785        }
   786      };
   787    };
   788  
   789    // Object Functions
   790    // ----------------
   791  
   792    // Retrieve the names of an object's properties.
   793    // Delegates to **ECMAScript 5**'s native `Object.keys`
   794    _.keys = function(obj) {
   795      if (!_.isObject(obj)) return [];
   796      if (nativeKeys) return nativeKeys(obj);
   797      var keys = [];
   798      for (var key in obj) if (_.has(obj, key)) keys.push(key);
   799      return keys;
   800    };
   801  
   802    // Retrieve the values of an object's properties.
   803    _.values = function(obj) {
   804      var keys = _.keys(obj);
   805      var length = keys.length;
   806      var values = new Array(length);
   807      for (var i = 0; i < length; i++) {
   808        values[i] = obj[keys[i]];
   809      }
   810      return values;
   811    };
   812  
   813    // Convert an object into a list of `[key, value]` pairs.
   814    _.pairs = function(obj) {
   815      var keys = _.keys(obj);
   816      var length = keys.length;
   817      var pairs = new Array(length);
   818      for (var i = 0; i < length; i++) {
   819        pairs[i] = [keys[i], obj[keys[i]]];
   820      }
   821      return pairs;
   822    };
   823  
   824    // Invert the keys and values of an object. The values must be serializable.
   825    _.invert = function(obj) {
   826      var result = {};
   827      var keys = _.keys(obj);
   828      for (var i = 0, length = keys.length; i < length; i++) {
   829        result[obj[keys[i]]] = keys[i];
   830      }
   831      return result;
   832    };
   833  
   834    // Return a sorted list of the function names available on the object.
   835    // Aliased as `methods`
   836    _.functions = _.methods = function(obj) {
   837      var names = [];
   838      for (var key in obj) {
   839        if (_.isFunction(obj[key])) names.push(key);
   840      }
   841      return names.sort();
   842    };
   843  
   844    // Extend a given object with all the properties in passed-in object(s).
   845    _.extend = function(obj) {
   846      each(slice.call(arguments, 1), function(source) {
   847        if (source) {
   848          for (var prop in source) {
   849            obj[prop] = source[prop];
   850          }
   851        }
   852      });
   853      return obj;
   854    };
   855  
   856    // Return a copy of the object only containing the whitelisted properties.
   857    _.pick = function(obj) {
   858      var copy = {};
   859      var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
   860      each(keys, function(key) {
   861        if (key in obj) copy[key] = obj[key];
   862      });
   863      return copy;
   864    };
   865  
   866     // Return a copy of the object without the blacklisted properties.
   867    _.omit = function(obj) {
   868      var copy = {};
   869      var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
   870      for (var key in obj) {
   871        if (!_.contains(keys, key)) copy[key] = obj[key];
   872      }
   873      return copy;
   874    };
   875  
   876    // Fill in a given object with default properties.
   877    _.defaults = function(obj) {
   878      each(slice.call(arguments, 1), function(source) {
   879        if (source) {
   880          for (var prop in source) {
   881            if (obj[prop] === void 0) obj[prop] = source[prop];
   882          }
   883        }
   884      });
   885      return obj;
   886    };
   887  
   888    // Create a (shallow-cloned) duplicate of an object.
   889    _.clone = function(obj) {
   890      if (!_.isObject(obj)) return obj;
   891      return _.isArray(obj) ? obj.slice() : _.extend({}, obj);
   892    };
   893  
   894    // Invokes interceptor with the obj, and then returns obj.
   895    // The primary purpose of this method is to "tap into" a method chain, in
   896    // order to perform operations on intermediate results within the chain.
   897    _.tap = function(obj, interceptor) {
   898      interceptor(obj);
   899      return obj;
   900    };
   901  
   902    // Internal recursive comparison function for `isEqual`.
   903    var eq = function(a, b, aStack, bStack) {
   904      // Identical objects are equal. `0 === -0`, but they aren't identical.
   905      // See the [Harmony `egal` proposal](http://wiki.ecmascript.org/doku.php?id=harmony:egal).
   906      if (a === b) return a !== 0 || 1 / a == 1 / b;
   907      // A strict comparison is necessary because `null == undefined`.
   908      if (a == null || b == null) return a === b;
   909      // Unwrap any wrapped objects.
   910      if (a instanceof _) a = a._wrapped;
   911      if (b instanceof _) b = b._wrapped;
   912      // Compare `[[Class]]` names.
   913      var className = toString.call(a);
   914      if (className != toString.call(b)) return false;
   915      switch (className) {
   916        // Strings, numbers, dates, and booleans are compared by value.
   917        case '[object String]':
   918          // Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
   919          // equivalent to `new String("5")`.
   920          return a == String(b);
   921        case '[object Number]':
   922          // `NaN`s are equivalent, but non-reflexive. An `egal` comparison is performed for
   923          // other numeric values.
   924          return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b);
   925        case '[object Date]':
   926        case '[object Boolean]':
   927          // Coerce dates and booleans to numeric primitive values. Dates are compared by their
   928          // millisecond representations. Note that invalid dates with millisecond representations
   929          // of `NaN` are not equivalent.
   930          return +a == +b;
   931        // RegExps are compared by their source patterns and flags.
   932        case '[object RegExp]':
   933          return a.source == b.source &&
   934                 a.global == b.global &&
   935                 a.multiline == b.multiline &&
   936                 a.ignoreCase == b.ignoreCase;
   937      }
   938      if (typeof a != 'object' || typeof b != 'object') return false;
   939      // Assume equality for cyclic structures. The algorithm for detecting cyclic
   940      // structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
   941      var length = aStack.length;
   942      while (length--) {
   943        // Linear search. Performance is inversely proportional to the number of
   944        // unique nested structures.
   945        if (aStack[length] == a) return bStack[length] == b;
   946      }
   947      // Objects with different constructors are not equivalent, but `Object`s
   948      // from different frames are.
   949      var aCtor = a.constructor, bCtor = b.constructor;
   950      if (aCtor !== bCtor && !(_.isFunction(aCtor) && (aCtor instanceof aCtor) &&
   951                               _.isFunction(bCtor) && (bCtor instanceof bCtor))
   952                          && ('constructor' in a && 'constructor' in b)) {
   953        return false;
   954      }
   955      // Add the first object to the stack of traversed objects.
   956      aStack.push(a);
   957      bStack.push(b);
   958      var size = 0, result = true;
   959      // Recursively compare objects and arrays.
   960      if (className == '[object Array]') {
   961        // Compare array lengths to determine if a deep comparison is necessary.
   962        size = a.length;
   963        result = size == b.length;
   964        if (result) {
   965          // Deep compare the contents, ignoring non-numeric properties.
   966          while (size--) {
   967            if (!(result = eq(a[size], b[size], aStack, bStack))) break;
   968          }
   969        }
   970      } else {
   971        // Deep compare objects.
   972        for (var key in a) {
   973          if (_.has(a, key)) {
   974            // Count the expected number of properties.
   975            size++;
   976            // Deep compare each member.
   977            if (!(result = _.has(b, key) && eq(a[key], b[key], aStack, bStack))) break;
   978          }
   979        }
   980        // Ensure that both objects contain the same number of properties.
   981        if (result) {
   982          for (key in b) {
   983            if (_.has(b, key) && !(size--)) break;
   984          }
   985          result = !size;
   986        }
   987      }
   988      // Remove the first object from the stack of traversed objects.
   989      aStack.pop();
   990      bStack.pop();
   991      return result;
   992    };
   993  
   994    // Perform a deep comparison to check if two objects are equal.
   995    _.isEqual = function(a, b) {
   996      return eq(a, b, [], []);
   997    };
   998  
   999    // Is a given array, string, or object empty?
  1000    // An "empty" object has no enumerable own-properties.
  1001    _.isEmpty = function(obj) {
  1002      if (obj == null) return true;
  1003      if (_.isArray(obj) || _.isString(obj)) return obj.length === 0;
  1004      for (var key in obj) if (_.has(obj, key)) return false;
  1005      return true;
  1006    };
  1007  
  1008    // Is a given value a DOM element?
  1009    _.isElement = function(obj) {
  1010      return !!(obj && obj.nodeType === 1);
  1011    };
  1012  
  1013    // Is a given value an array?
  1014    // Delegates to ECMA5's native Array.isArray
  1015    _.isArray = nativeIsArray || function(obj) {
  1016      return toString.call(obj) == '[object Array]';
  1017    };
  1018  
  1019    // Is a given variable an object?
  1020    _.isObject = function(obj) {
  1021      return obj === Object(obj);
  1022    };
  1023  
  1024    // Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp.
  1025    each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp'], function(name) {
  1026      _['is' + name] = function(obj) {
  1027        return toString.call(obj) == '[object ' + name + ']';
  1028      };
  1029    });
  1030  
  1031    // Define a fallback version of the method in browsers (ahem, IE), where
  1032    // there isn't any inspectable "Arguments" type.
  1033    if (!_.isArguments(arguments)) {
  1034      _.isArguments = function(obj) {
  1035        return !!(obj && _.has(obj, 'callee'));
  1036      };
  1037    }
  1038  
  1039    // Optimize `isFunction` if appropriate.
  1040    if (typeof (/./) !== 'function') {
  1041      _.isFunction = function(obj) {
  1042        return typeof obj === 'function';
  1043      };
  1044    }
  1045  
  1046    // Is a given object a finite number?
  1047    _.isFinite = function(obj) {
  1048      return isFinite(obj) && !isNaN(parseFloat(obj));
  1049    };
  1050  
  1051    // Is the given value `NaN`? (NaN is the only number which does not equal itself).
  1052    _.isNaN = function(obj) {
  1053      return _.isNumber(obj) && obj != +obj;
  1054    };
  1055  
  1056    // Is a given value a boolean?
  1057    _.isBoolean = function(obj) {
  1058      return obj === true || obj === false || toString.call(obj) == '[object Boolean]';
  1059    };
  1060  
  1061    // Is a given value equal to null?
  1062    _.isNull = function(obj) {
  1063      return obj === null;
  1064    };
  1065  
  1066    // Is a given variable undefined?
  1067    _.isUndefined = function(obj) {
  1068      return obj === void 0;
  1069    };
  1070  
  1071    // Shortcut function for checking if an object has a given property directly
  1072    // on itself (in other words, not on a prototype).
  1073    _.has = function(obj, key) {
  1074      return hasOwnProperty.call(obj, key);
  1075    };
  1076  
  1077    // Utility Functions
  1078    // -----------------
  1079  
  1080    // Run Underscore.js in *noConflict* mode, returning the `_` variable to its
  1081    // previous owner. Returns a reference to the Underscore object.
  1082    _.noConflict = function() {
  1083      root._ = previousUnderscore;
  1084      return this;
  1085    };
  1086  
  1087    // Keep the identity function around for default iterators.
  1088    _.identity = function(value) {
  1089      return value;
  1090    };
  1091  
  1092    _.constant = function(value) {
  1093      return function () {
  1094        return value;
  1095      };
  1096    };
  1097  
  1098    _.property = function(key) {
  1099      return function(obj) {
  1100        return obj[key];
  1101      };
  1102    };
  1103  
  1104    // Returns a predicate for checking whether an object has a given set of `key:value` pairs.
  1105    _.matches = function(attrs) {
  1106      return function(obj) {
  1107        if (obj === attrs) return true; //avoid comparing an object to itself.
  1108        for (var key in attrs) {
  1109          if (attrs[key] !== obj[key])
  1110            return false;
  1111        }
  1112        return true;
  1113      }
  1114    };
  1115  
  1116    // Run a function **n** times.
  1117    _.times = function(n, iterator, context) {
  1118      var accum = Array(Math.max(0, n));
  1119      for (var i = 0; i < n; i++) accum[i] = iterator.call(context, i);
  1120      return accum;
  1121    };
  1122  
  1123    // Return a random integer between min and max (inclusive).
  1124    _.random = function(min, max) {
  1125      if (max == null) {
  1126        max = min;
  1127        min = 0;
  1128      }
  1129      return min + Math.floor(Math.random() * (max - min + 1));
  1130    };
  1131  
  1132    // A (possibly faster) way to get the current timestamp as an integer.
  1133    _.now = Date.now || function() { return new Date().getTime(); };
  1134  
  1135    // List of HTML entities for escaping.
  1136    var entityMap = {
  1137      escape: {
  1138        '&': '&amp;',
  1139        '<': '&lt;',
  1140        '>': '&gt;',
  1141        '"': '&quot;',
  1142        "'": '&#x27;'
  1143      }
  1144    };
  1145    entityMap.unescape = _.invert(entityMap.escape);
  1146  
  1147    // Regexes containing the keys and values listed immediately above.
  1148    var entityRegexes = {
  1149      escape:   new RegExp('[' + _.keys(entityMap.escape).join('') + ']', 'g'),
  1150      unescape: new RegExp('(' + _.keys(entityMap.unescape).join('|') + ')', 'g')
  1151    };
  1152  
  1153    // Functions for escaping and unescaping strings to/from HTML interpolation.
  1154    _.each(['escape', 'unescape'], function(method) {
  1155      _[method] = function(string) {
  1156        if (string == null) return '';
  1157        return ('' + string).replace(entityRegexes[method], function(match) {
  1158          return entityMap[method][match];
  1159        });
  1160      };
  1161    });
  1162  
  1163    // If the value of the named `property` is a function then invoke it with the
  1164    // `object` as context; otherwise, return it.
  1165    _.result = function(object, property) {
  1166      if (object == null) return void 0;
  1167      var value = object[property];
  1168      return _.isFunction(value) ? value.call(object) : value;
  1169    };
  1170  
  1171    // Add your own custom functions to the Underscore object.
  1172    _.mixin = function(obj) {
  1173      each(_.functions(obj), function(name) {
  1174        var func = _[name] = obj[name];
  1175        _.prototype[name] = function() {
  1176          var args = [this._wrapped];
  1177          push.apply(args, arguments);
  1178          return result.call(this, func.apply(_, args));
  1179        };
  1180      });
  1181    };
  1182  
  1183    // Generate a unique integer id (unique within the entire client session).
  1184    // Useful for temporary DOM ids.
  1185    var idCounter = 0;
  1186    _.uniqueId = function(prefix) {
  1187      var id = ++idCounter + '';
  1188      return prefix ? prefix + id : id;
  1189    };
  1190  
  1191    // By default, Underscore uses ERB-style template delimiters, change the
  1192    // following template settings to use alternative delimiters.
  1193    _.templateSettings = {
  1194      evaluate    : /<%([\s\S]+?)%>/g,
  1195      interpolate : /<%=([\s\S]+?)%>/g,
  1196      escape      : /<%-([\s\S]+?)%>/g
  1197    };
  1198  
  1199    // When customizing `templateSettings`, if you don't want to define an
  1200    // interpolation, evaluation or escaping regex, we need one that is
  1201    // guaranteed not to match.
  1202    var noMatch = /(.)^/;
  1203  
  1204    // Certain characters need to be escaped so that they can be put into a
  1205    // string literal.
  1206    var escapes = {
  1207      "'":      "'",
  1208      '\\':     '\\',
  1209      '\r':     'r',
  1210      '\n':     'n',
  1211      '\t':     't',
  1212      '\u2028': 'u2028',
  1213      '\u2029': 'u2029'
  1214    };
  1215  
  1216    var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
  1217  
  1218    // JavaScript micro-templating, similar to John Resig's implementation.
  1219    // Underscore templating handles arbitrary delimiters, preserves whitespace,
  1220    // and correctly escapes quotes within interpolated code.
  1221    _.template = function(text, data, settings) {
  1222      var render;
  1223      settings = _.defaults({}, settings, _.templateSettings);
  1224  
  1225      // Combine delimiters into one regular expression via alternation.
  1226      var matcher = new RegExp([
  1227        (settings.escape || noMatch).source,
  1228        (settings.interpolate || noMatch).source,
  1229        (settings.evaluate || noMatch).source
  1230      ].join('|') + '|$', 'g');
  1231  
  1232      // Compile the template source, escaping string literals appropriately.
  1233      var index = 0;
  1234      var source = "__p+='";
  1235      text.replace(matcher, function(match, escape, interpolate, evaluate, offset) {
  1236        source += text.slice(index, offset)
  1237          .replace(escaper, function(match) { return '\\' + escapes[match]; });
  1238  
  1239        if (escape) {
  1240          source += "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'";
  1241        }
  1242        if (interpolate) {
  1243          source += "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'";
  1244        }
  1245        if (evaluate) {
  1246          source += "';\n" + evaluate + "\n__p+='";
  1247        }
  1248        index = offset + match.length;
  1249        return match;
  1250      });
  1251      source += "';\n";
  1252  
  1253      // If a variable is not specified, place data values in local scope.
  1254      if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';
  1255  
  1256      source = "var __t,__p='',__j=Array.prototype.join," +
  1257        "print=function(){__p+=__j.call(arguments,'');};\n" +
  1258        source + "return __p;\n";
  1259  
  1260      try {
  1261        render = new Function(settings.variable || 'obj', '_', source);
  1262      } catch (e) {
  1263        e.source = source;
  1264        throw e;
  1265      }
  1266  
  1267      if (data) return render(data, _);
  1268      var template = function(data) {
  1269        return render.call(this, data, _);
  1270      };
  1271  
  1272      // Provide the compiled function source as a convenience for precompilation.
  1273      template.source = 'function(' + (settings.variable || 'obj') + '){\n' + source + '}';
  1274  
  1275      return template;
  1276    };
  1277  
  1278    // Add a "chain" function, which will delegate to the wrapper.
  1279    _.chain = function(obj) {
  1280      return _(obj).chain();
  1281    };
  1282  
  1283    // OOP
  1284    // ---------------
  1285    // If Underscore is called as a function, it returns a wrapped object that
  1286    // can be used OO-style. This wrapper holds altered versions of all the
  1287    // underscore functions. Wrapped objects may be chained.
  1288  
  1289    // Helper function to continue chaining intermediate results.
  1290    var result = function(obj) {
  1291      return this._chain ? _(obj).chain() : obj;
  1292    };
  1293  
  1294    // Add all of the Underscore functions to the wrapper object.
  1295    _.mixin(_);
  1296  
  1297    // Add all mutator Array functions to the wrapper.
  1298    each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) {
  1299      var method = ArrayProto[name];
  1300      _.prototype[name] = function() {
  1301        var obj = this._wrapped;
  1302        method.apply(obj, arguments);
  1303        if ((name == 'shift' || name == 'splice') && obj.length === 0) delete obj[0];
  1304        return result.call(this, obj);
  1305      };
  1306    });
  1307  
  1308    // Add all accessor Array functions to the wrapper.
  1309    each(['concat', 'join', 'slice'], function(name) {
  1310      var method = ArrayProto[name];
  1311      _.prototype[name] = function() {
  1312        return result.call(this, method.apply(this._wrapped, arguments));
  1313      };
  1314    });
  1315  
  1316    _.extend(_.prototype, {
  1317  
  1318      // Start chaining a wrapped Underscore object.
  1319      chain: function() {
  1320        this._chain = true;
  1321        return this;
  1322      },
  1323  
  1324      // Extracts the result from a wrapped and chained object.
  1325      value: function() {
  1326        return this._wrapped;
  1327      }
  1328  
  1329    });
  1330  
  1331    // AMD registration happens at the end for compatibility with AMD loaders
  1332    // that may not enforce next-turn semantics on modules. Even though general
  1333    // practice for AMD registration is to be anonymous, underscore registers
  1334    // as a named module because, like jQuery, it is a base library that is
  1335    // popular enough to be bundled in a third party lib, but not be part of
  1336    // an AMD load request. Those cases could generate an error when an
  1337    // anonymous define() is called outside of a loader request.
  1338    if (typeof define === 'function' && define.amd) {
  1339      define('underscore', [], function() {
  1340        return _;
  1341      });
  1342    }
  1343  }).call(this);