/*!
 * warmsea JavaScript Library v1.0.0
 *
 * Copyright 2009, 2014 Su Su
 * Released under the MIT license
 *
 * Date: 2014-10-24
 */


//// START OF THE underscore.js SOURCE CODE

//     Underscore.js 1.7.0
//     http://underscorejs.org
//     (c) 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
//     Underscore may be freely distributed under the MIT license.

(function() {

  // Baseline setup
  // --------------

  // Establish the root object, `window` in the browser, or `exports` on the server.
  var root = this;

  // Save the previous value of the `_` variable.
  var previousUnderscore = root._;

  // Save bytes in the minified (but not gzipped) version:
  var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype;

  // Create quick reference variables for speed access to core prototypes.
  var
    push             = ArrayProto.push,
    slice            = ArrayProto.slice,
    concat           = ArrayProto.concat,
    toString         = ObjProto.toString,
    hasOwnProperty   = ObjProto.hasOwnProperty;

  // All **ECMAScript 5** native function implementations that we hope to use
  // are declared here.
  var
    nativeIsArray      = Array.isArray,
    nativeKeys         = Object.keys,
    nativeBind         = FuncProto.bind;

  // Create a safe reference to the Underscore object for use below.
  var _ = function(obj) {
    if (obj instanceof _) return obj;
    if (!(this instanceof _)) return new _(obj);
    this._wrapped = obj;
  };

  // Export the Underscore object for **Node.js**, with
  // backwards-compatibility for the old `require()` API. If we're in
  // the browser, add `_` as a global object.
  if (typeof exports !== 'undefined') {
    if (typeof module !== 'undefined' && module.exports) {
      exports = module.exports = _;
    }
    exports._ = _;
  } else {
    root._ = _;
  }

  // Current version.
  _.VERSION = '1.7.0';

  // Internal function that returns an efficient (for current engines) version
  // of the passed-in callback, to be repeatedly applied in other Underscore
  // functions.
  var createCallback = function(func, context, argCount) {
    if (context === void 0) return func;
    switch (argCount == null ? 3 : argCount) {
      case 1: return function(value) {
        return func.call(context, value);
      };
      case 2: return function(value, other) {
        return func.call(context, value, other);
      };
      case 3: return function(value, index, collection) {
        return func.call(context, value, index, collection);
      };
      case 4: return function(accumulator, value, index, collection) {
        return func.call(context, accumulator, value, index, collection);
      };
    }
    return function() {
      return func.apply(context, arguments);
    };
  };

  // A mostly-internal function to generate callbacks that can be applied
  // to each element in a collection, returning the desired result — either
  // identity, an arbitrary callback, a property matcher, or a property accessor.
  _.iteratee = function(value, context, argCount) {
    if (value == null) return _.identity;
    if (_.isFunction(value)) return createCallback(value, context, argCount);
    if (_.isObject(value)) return _.matches(value);
    return _.property(value);
  };

  // Collection Functions
  // --------------------

  // The cornerstone, an `each` implementation, aka `forEach`.
  // Handles raw objects in addition to array-likes. Treats all
  // sparse array-likes as if they were dense.
  _.each = _.forEach = function(obj, iteratee, context) {
    if (obj == null) return obj;
    iteratee = createCallback(iteratee, context);
    var i, length = obj.length;
    if (length === +length) {
      for (i = 0; i < length; i++) {
        iteratee(obj[i], i, obj);
      }
    } else {
      var keys = _.keys(obj);
      for (i = 0, length = keys.length; i < length; i++) {
        iteratee(obj[keys[i]], keys[i], obj);
      }
    }
    return obj;
  };

  // Return the results of applying the iteratee to each element.
  _.map = _.collect = function(obj, iteratee, context) {
    if (obj == null) return [];
    iteratee = _.iteratee(iteratee, context);
    var keys = obj.length !== +obj.length && _.keys(obj),
        length = (keys || obj).length,
        results = Array(length),
        currentKey;
    for (var index = 0; index < length; index++) {
      currentKey = keys ? keys[index] : index;
      results[index] = iteratee(obj[currentKey], currentKey, obj);
    }
    return results;
  };

  var reduceError = 'Reduce of empty array with no initial value';

  // **Reduce** builds up a single result from a list of values, aka `inject`,
  // or `foldl`.
  _.reduce = _.foldl = _.inject = function(obj, iteratee, memo, context) {
    if (obj == null) obj = [];
    iteratee = createCallback(iteratee, context, 4);
    var keys = obj.length !== +obj.length && _.keys(obj),
        length = (keys || obj).length,
        index = 0, currentKey;
    if (arguments.length < 3) {
      if (!length) throw new TypeError(reduceError);
      memo = obj[keys ? keys[index++] : index++];
    }
    for (; index < length; index++) {
      currentKey = keys ? keys[index] : index;
      memo = iteratee(memo, obj[currentKey], currentKey, obj);
    }
    return memo;
  };

  // The right-associative version of reduce, also known as `foldr`.
  _.reduceRight = _.foldr = function(obj, iteratee, memo, context) {
    if (obj == null) obj = [];
    iteratee = createCallback(iteratee, context, 4);
    var keys = obj.length !== + obj.length && _.keys(obj),
        index = (keys || obj).length,
        currentKey;
    if (arguments.length < 3) {
      if (!index) throw new TypeError(reduceError);
      memo = obj[keys ? keys[--index] : --index];
    }
    while (index--) {
      currentKey = keys ? keys[index] : index;
      memo = iteratee(memo, obj[currentKey], currentKey, obj);
    }
    return memo;
  };

  // Return the first value which passes a truth test. Aliased as `detect`.
  _.find = _.detect = function(obj, predicate, context) {
    var result;
    predicate = _.iteratee(predicate, context);
    _.some(obj, function(value, index, list) {
      if (predicate(value, index, list)) {
        result = value;
        return true;
      }
    });
    return result;
  };

  // Return all the elements that pass a truth test.
  // Aliased as `select`.
  _.filter = _.select = function(obj, predicate, context) {
    var results = [];
    if (obj == null) return results;
    predicate = _.iteratee(predicate, context);
    _.each(obj, function(value, index, list) {
      if (predicate(value, index, list)) results.push(value);
    });
    return results;
  };

  // Return all the elements for which a truth test fails.
  _.reject = function(obj, predicate, context) {
    return _.filter(obj, _.negate(_.iteratee(predicate)), context);
  };

  // Determine whether all of the elements match a truth test.
  // Aliased as `all`.
  _.every = _.all = function(obj, predicate, context) {
    if (obj == null) return true;
    predicate = _.iteratee(predicate, context);
    var keys = obj.length !== +obj.length && _.keys(obj),
        length = (keys || obj).length,
        index, currentKey;
    for (index = 0; index < length; index++) {
      currentKey = keys ? keys[index] : index;
      if (!predicate(obj[currentKey], currentKey, obj)) return false;
    }
    return true;
  };

  // Determine if at least one element in the object matches a truth test.
  // Aliased as `any`.
  _.some = _.any = function(obj, predicate, context) {
    if (obj == null) return false;
    predicate = _.iteratee(predicate, context);
    var keys = obj.length !== +obj.length && _.keys(obj),
        length = (keys || obj).length,
        index, currentKey;
    for (index = 0; index < length; index++) {
      currentKey = keys ? keys[index] : index;
      if (predicate(obj[currentKey], currentKey, obj)) return true;
    }
    return false;
  };

  // Determine if the array or object contains a given value (using `===`).
  // Aliased as `include`.
  _.contains = _.include = function(obj, target) {
    if (obj == null) return false;
    if (obj.length !== +obj.length) obj = _.values(obj);
    return _.indexOf(obj, target) >= 0;
  };

  // Invoke a method (with arguments) on every item in a collection.
  _.invoke = function(obj, method) {
    var args = slice.call(arguments, 2);
    var isFunc = _.isFunction(method);
    return _.map(obj, function(value) {
      return (isFunc ? method : value[method]).apply(value, args);
    });
  };

  // Convenience version of a common use case of `map`: fetching a property.
  _.pluck = function(obj, key) {
    return _.map(obj, _.property(key));
  };

  // Convenience version of a common use case of `filter`: selecting only objects
  // containing specific `key:value` pairs.
  _.where = function(obj, attrs) {
    return _.filter(obj, _.matches(attrs));
  };

  // Convenience version of a common use case of `find`: getting the first object
  // containing specific `key:value` pairs.
  _.findWhere = function(obj, attrs) {
    return _.find(obj, _.matches(attrs));
  };

  // Return the maximum element (or element-based computation).
  _.max = function(obj, iteratee, context) {
    var result = -Infinity, lastComputed = -Infinity,
        value, computed;
    if (iteratee == null && obj != null) {
      obj = obj.length === +obj.length ? obj : _.values(obj);
      for (var i = 0, length = obj.length; i < length; i++) {
        value = obj[i];
        if (value > result) {
          result = value;
        }
      }
    } else {
      iteratee = _.iteratee(iteratee, context);
      _.each(obj, function(value, index, list) {
        computed = iteratee(value, index, list);
        if (computed > lastComputed || computed === -Infinity && result === -Infinity) {
          result = value;
          lastComputed = computed;
        }
      });
    }
    return result;
  };

  // Return the minimum element (or element-based computation).
  _.min = function(obj, iteratee, context) {
    var result = Infinity, lastComputed = Infinity,
        value, computed;
    if (iteratee == null && obj != null) {
      obj = obj.length === +obj.length ? obj : _.values(obj);
      for (var i = 0, length = obj.length; i < length; i++) {
        value = obj[i];
        if (value < result) {
          result = value;
        }
      }
    } else {
      iteratee = _.iteratee(iteratee, context);
      _.each(obj, function(value, index, list) {
        computed = iteratee(value, index, list);
        if (computed < lastComputed || computed === Infinity && result === Infinity) {
          result = value;
          lastComputed = computed;
        }
      });
    }
    return result;
  };

  // Shuffle a collection, using the modern version of the
  // [Fisher-Yates shuffle](http://en.wikipedia.org/wiki/Fisher–Yates_shuffle).
  _.shuffle = function(obj) {
    var set = obj && obj.length === +obj.length ? obj : _.values(obj);
    var length = set.length;
    var shuffled = Array(length);
    for (var index = 0, rand; index < length; index++) {
      rand = _.random(0, index);
      if (rand !== index) shuffled[index] = shuffled[rand];
      shuffled[rand] = set[index];
    }
    return shuffled;
  };

  // Sample **n** random values from a collection.
  // If **n** is not specified, returns a single random element.
  // The internal `guard` argument allows it to work with `map`.
  _.sample = function(obj, n, guard) {
    if (n == null || guard) {
      if (obj.length !== +obj.length) obj = _.values(obj);
      return obj[_.random(obj.length - 1)];
    }
    return _.shuffle(obj).slice(0, Math.max(0, n));
  };

  // Sort the object's values by a criterion produced by an iteratee.
  _.sortBy = function(obj, iteratee, context) {
    iteratee = _.iteratee(iteratee, context);
    return _.pluck(_.map(obj, function(value, index, list) {
      return {
        value: value,
        index: index,
        criteria: iteratee(value, index, list)
      };
    }).sort(function(left, right) {
      var a = left.criteria;
      var b = right.criteria;
      if (a !== b) {
        if (a > b || a === void 0) return 1;
        if (a < b || b === void 0) return -1;
      }
      return left.index - right.index;
    }), 'value');
  };

  // An internal function used for aggregate "group by" operations.
  var group = function(behavior) {
    return function(obj, iteratee, context) {
      var result = {};
      iteratee = _.iteratee(iteratee, context);
      _.each(obj, function(value, index) {
        var key = iteratee(value, index, obj);
        behavior(result, value, key);
      });
      return result;
    };
  };

  // Groups the object's values by a criterion. Pass either a string attribute
  // to group by, or a function that returns the criterion.
  _.groupBy = group(function(result, value, key) {
    if (_.has(result, key)) result[key].push(value); else result[key] = [value];
  });

  // Indexes the object's values by a criterion, similar to `groupBy`, but for
  // when you know that your index values will be unique.
  _.indexBy = group(function(result, value, key) {
    result[key] = value;
  });

  // Counts instances of an object that group by a certain criterion. Pass
  // either a string attribute to count by, or a function that returns the
  // criterion.
  _.countBy = group(function(result, value, key) {
    if (_.has(result, key)) result[key]++; else result[key] = 1;
  });

  // Use a comparator function to figure out the smallest index at which
  // an object should be inserted so as to maintain order. Uses binary search.
  _.sortedIndex = function(array, obj, iteratee, context) {
    iteratee = _.iteratee(iteratee, context, 1);
    var value = iteratee(obj);
    var low = 0, high = array.length;
    while (low < high) {
      var mid = low + high >>> 1;
      if (iteratee(array[mid]) < value) low = mid + 1; else high = mid;
    }
    return low;
  };

  // Safely create a real, live array from anything iterable.
  _.toArray = function(obj) {
    if (!obj) return [];
    if (_.isArray(obj)) return slice.call(obj);
    if (obj.length === +obj.length) return _.map(obj, _.identity);
    return _.values(obj);
  };

  // Return the number of elements in an object.
  _.size = function(obj) {
    if (obj == null) return 0;
    return obj.length === +obj.length ? obj.length : _.keys(obj).length;
  };

  // Split a collection into two arrays: one whose elements all satisfy the given
  // predicate, and one whose elements all do not satisfy the predicate.
  _.partition = function(obj, predicate, context) {
    predicate = _.iteratee(predicate, context);
    var pass = [], fail = [];
    _.each(obj, function(value, key, obj) {
      (predicate(value, key, obj) ? pass : fail).push(value);
    });
    return [pass, fail];
  };

  // Array Functions
  // ---------------

  // Get the first element of an array. Passing **n** will return the first N
  // values in the array. Aliased as `head` and `take`. The **guard** check
  // allows it to work with `_.map`.
  _.first = _.head = _.take = function(array, n, guard) {
    if (array == null) return void 0;
    if (n == null || guard) return array[0];
    if (n < 0) return [];
    return slice.call(array, 0, n);
  };

  // Returns everything but the last entry of the array. Especially useful on
  // the arguments object. Passing **n** will return all the values in
  // the array, excluding the last N. The **guard** check allows it to work with
  // `_.map`.
  _.initial = function(array, n, guard) {
    return slice.call(array, 0, Math.max(0, array.length - (n == null || guard ? 1 : n)));
  };

  // Get the last element of an array. Passing **n** will return the last N
  // values in the array. The **guard** check allows it to work with `_.map`.
  _.last = function(array, n, guard) {
    if (array == null) return void 0;
    if (n == null || guard) return array[array.length - 1];
    return slice.call(array, Math.max(array.length - n, 0));
  };

  // Returns everything but the first entry of the array. Aliased as `tail` and `drop`.
  // Especially useful on the arguments object. Passing an **n** will return
  // the rest N values in the array. The **guard**
  // check allows it to work with `_.map`.
  _.rest = _.tail = _.drop = function(array, n, guard) {
    return slice.call(array, n == null || guard ? 1 : n);
  };

  // Trim out all falsy values from an array.
  _.compact = function(array) {
    return _.filter(array, _.identity);
  };

  // Internal implementation of a recursive `flatten` function.
  var flatten = function(input, shallow, strict, output) {
    if (shallow && _.every(input, _.isArray)) {
      return concat.apply(output, input);
    }
    for (var i = 0, length = input.length; i < length; i++) {
      var value = input[i];
      if (!_.isArray(value) && !_.isArguments(value)) {
        if (!strict) output.push(value);
      } else if (shallow) {
        push.apply(output, value);
      } else {
        flatten(value, shallow, strict, output);
      }
    }
    return output;
  };

  // Flatten out an array, either recursively (by default), or just one level.
  _.flatten = function(array, shallow) {
    return flatten(array, shallow, false, []);
  };

  // Return a version of the array that does not contain the specified value(s).
  _.without = function(array) {
    return _.difference(array, slice.call(arguments, 1));
  };

  // Produce a duplicate-free version of the array. If the array has already
  // been sorted, you have the option of using a faster algorithm.
  // Aliased as `unique`.
  _.uniq = _.unique = function(array, isSorted, iteratee, context) {
    if (array == null) return [];
    if (!_.isBoolean(isSorted)) {
      context = iteratee;
      iteratee = isSorted;
      isSorted = false;
    }
    if (iteratee != null) iteratee = _.iteratee(iteratee, context);
    var result = [];
    var seen = [];
    for (var i = 0, length = array.length; i < length; i++) {
      var value = array[i];
      if (isSorted) {
        if (!i || seen !== value) result.push(value);
        seen = value;
      } else if (iteratee) {
        var computed = iteratee(value, i, array);
        if (_.indexOf(seen, computed) < 0) {
          seen.push(computed);
          result.push(value);
        }
      } else if (_.indexOf(result, value) < 0) {
        result.push(value);
      }
    }
    return result;
  };

  // Produce an array that contains the union: each distinct element from all of
  // the passed-in arrays.
  _.union = function() {
    return _.uniq(flatten(arguments, true, true, []));
  };

  // Produce an array that contains every item shared between all the
  // passed-in arrays.
  _.intersection = function(array) {
    if (array == null) return [];
    var result = [];
    var argsLength = arguments.length;
    for (var i = 0, length = array.length; i < length; i++) {
      var item = array[i];
      if (_.contains(result, item)) continue;
      for (var j = 1; j < argsLength; j++) {
        if (!_.contains(arguments[j], item)) break;
      }
      if (j === argsLength) result.push(item);
    }
    return result;
  };

  // Take the difference between one array and a number of other arrays.
  // Only the elements present in just the first array will remain.
  _.difference = function(array) {
    var rest = flatten(slice.call(arguments, 1), true, true, []);
    return _.filter(array, function(value){
      return !_.contains(rest, value);
    });
  };

  // Zip together multiple lists into a single array -- elements that share
  // an index go together.
  _.zip = function(array) {
    if (array == null) return [];
    var length = _.max(arguments, 'length').length;
    var results = Array(length);
    for (var i = 0; i < length; i++) {
      results[i] = _.pluck(arguments, i);
    }
    return results;
  };

  // Converts lists into objects. Pass either a single array of `[key, value]`
  // pairs, or two parallel arrays of the same length -- one of keys, and one of
  // the corresponding values.
  _.object = function(list, values) {
    if (list == null) return {};
    var result = {};
    for (var i = 0, length = list.length; i < length; i++) {
      if (values) {
        result[list[i]] = values[i];
      } else {
        result[list[i][0]] = list[i][1];
      }
    }
    return result;
  };

  // Return the position of the first occurrence of an item in an array,
  // or -1 if the item is not included in the array.
  // If the array is large and already in sort order, pass `true`
  // for **isSorted** to use binary search.
  _.indexOf = function(array, item, isSorted) {
    if (array == null) return -1;
    var i = 0, length = array.length;
    if (isSorted) {
      if (typeof isSorted == 'number') {
        i = isSorted < 0 ? Math.max(0, length + isSorted) : isSorted;
      } else {
        i = _.sortedIndex(array, item);
        return array[i] === item ? i : -1;
      }
    }
    for (; i < length; i++) if (array[i] === item) return i;
    return -1;
  };

  _.lastIndexOf = function(array, item, from) {
    if (array == null) return -1;
    var idx = array.length;
    if (typeof from == 'number') {
      idx = from < 0 ? idx + from + 1 : Math.min(idx, from + 1);
    }
    while (--idx >= 0) if (array[idx] === item) return idx;
    return -1;
  };

  // Generate an integer Array containing an arithmetic progression. A port of
  // the native Python `range()` function. See
  // [the Python documentation](http://docs.python.org/library/functions.html#range).
  _.range = function(start, stop, step) {
    if (arguments.length <= 1) {
      stop = start || 0;
      start = 0;
    }
    step = step || 1;

    var length = Math.max(Math.ceil((stop - start) / step), 0);
    var range = Array(length);

    for (var idx = 0; idx < length; idx++, start += step) {
      range[idx] = start;
    }

    return range;
  };

  // Function (ahem) Functions
  // ------------------

  // Reusable constructor function for prototype setting.
  var Ctor = function(){};

  // Create a function bound to a given object (assigning `this`, and arguments,
  // optionally). Delegates to **ECMAScript 5**'s native `Function.bind` if
  // available.
  _.bind = function(func, context) {
    var args, bound;
    if (nativeBind && func.bind === nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
    if (!_.isFunction(func)) throw new TypeError('Bind must be called on a function');
    args = slice.call(arguments, 2);
    bound = function() {
      if (!(this instanceof bound)) return func.apply(context, args.concat(slice.call(arguments)));
      Ctor.prototype = func.prototype;
      var self = new Ctor;
      Ctor.prototype = null;
      var result = func.apply(self, args.concat(slice.call(arguments)));
      if (_.isObject(result)) return result;
      return self;
    };
    return bound;
  };

  // Partially apply a function by creating a version that has had some of its
  // arguments pre-filled, without changing its dynamic `this` context. _ acts
  // as a placeholder, allowing any combination of arguments to be pre-filled.
  _.partial = function(func) {
    var boundArgs = slice.call(arguments, 1);
    return function() {
      var position = 0;
      var args = boundArgs.slice();
      for (var i = 0, length = args.length; i < length; i++) {
        if (args[i] === _) args[i] = arguments[position++];
      }
      while (position < arguments.length) args.push(arguments[position++]);
      return func.apply(this, args);
    };
  };

  // Bind a number of an object's methods to that object. Remaining arguments
  // are the method names to be bound. Useful for ensuring that all callbacks
  // defined on an object belong to it.
  _.bindAll = function(obj) {
    var i, length = arguments.length, key;
    if (length <= 1) throw new Error('bindAll must be passed function names');
    for (i = 1; i < length; i++) {
      key = arguments[i];
      obj[key] = _.bind(obj[key], obj);
    }
    return obj;
  };

  // Memoize an expensive function by storing its results.
  _.memoize = function(func, hasher) {
    var memoize = function(key) {
      var cache = memoize.cache;
      var address = hasher ? hasher.apply(this, arguments) : key;
      if (!_.has(cache, address)) cache[address] = func.apply(this, arguments);
      return cache[address];
    };
    memoize.cache = {};
    return memoize;
  };

  // Delays a function for the given number of milliseconds, and then calls
  // it with the arguments supplied.
  _.delay = function(func, wait) {
    var args = slice.call(arguments, 2);
    return setTimeout(function(){
      return func.apply(null, args);
    }, wait);
  };

  // Defers a function, scheduling it to run after the current call stack has
  // cleared.
  _.defer = function(func) {
    return _.delay.apply(_, [func, 1].concat(slice.call(arguments, 1)));
  };

  // Returns a function, that, when invoked, will only be triggered at most once
  // during a given window of time. Normally, the throttled function will run
  // as much as it can, without ever going more than once per `wait` duration;
  // but if you'd like to disable the execution on the leading edge, pass
  // `{leading: false}`. To disable execution on the trailing edge, ditto.
  _.throttle = function(func, wait, options) {
    var context, args, result;
    var timeout = null;
    var previous = 0;
    if (!options) options = {};
    var later = function() {
      previous = options.leading === false ? 0 : _.now();
      timeout = null;
      result = func.apply(context, args);
      if (!timeout) context = args = null;
    };
    return function() {
      var now = _.now();
      if (!previous && options.leading === false) previous = now;
      var remaining = wait - (now - previous);
      context = this;
      args = arguments;
      if (remaining <= 0 || remaining > wait) {
        clearTimeout(timeout);
        timeout = null;
        previous = now;
        result = func.apply(context, args);
        if (!timeout) context = args = null;
      } else if (!timeout && options.trailing !== false) {
        timeout = setTimeout(later, remaining);
      }
      return result;
    };
  };

  // Returns a function, that, as long as it continues to be invoked, will not
  // be triggered. The function will be called after it stops being called for
  // N milliseconds. If `immediate` is passed, trigger the function on the
  // leading edge, instead of the trailing.
  _.debounce = function(func, wait, immediate) {
    var timeout, args, context, timestamp, result;

    var later = function() {
      var last = _.now() - timestamp;

      if (last < wait && last > 0) {
        timeout = setTimeout(later, wait - last);
      } else {
        timeout = null;
        if (!immediate) {
          result = func.apply(context, args);
          if (!timeout) context = args = null;
        }
      }
    };

    return function() {
      context = this;
      args = arguments;
      timestamp = _.now();
      var callNow = immediate && !timeout;
      if (!timeout) timeout = setTimeout(later, wait);
      if (callNow) {
        result = func.apply(context, args);
        context = args = null;
      }

      return result;
    };
  };

  // Returns the first function passed as an argument to the second,
  // allowing you to adjust arguments, run code before and after, and
  // conditionally execute the original function.
  _.wrap = function(func, wrapper) {
    return _.partial(wrapper, func);
  };

  // Returns a negated version of the passed-in predicate.
  _.negate = function(predicate) {
    return function() {
      return !predicate.apply(this, arguments);
    };
  };

  // Returns a function that is the composition of a list of functions, each
  // consuming the return value of the function that follows.
  _.compose = function() {
    var args = arguments;
    var start = args.length - 1;
    return function() {
      var i = start;
      var result = args[start].apply(this, arguments);
      while (i--) result = args[i].call(this, result);
      return result;
    };
  };

  // Returns a function that will only be executed after being called N times.
  _.after = function(times, func) {
    return function() {
      if (--times < 1) {
        return func.apply(this, arguments);
      }
    };
  };

  // Returns a function that will only be executed before being called N times.
  _.before = function(times, func) {
    var memo;
    return function() {
      if (--times > 0) {
        memo = func.apply(this, arguments);
      } else {
        func = null;
      }
      return memo;
    };
  };

  // Returns a function that will be executed at most one time, no matter how
  // often you call it. Useful for lazy initialization.
  _.once = _.partial(_.before, 2);

  // Object Functions
  // ----------------

  // Retrieve the names of an object's properties.
  // Delegates to **ECMAScript 5**'s native `Object.keys`
  _.keys = function(obj) {
    if (!_.isObject(obj)) return [];
    if (nativeKeys) return nativeKeys(obj);
    var keys = [];
    for (var key in obj) if (_.has(obj, key)) keys.push(key);
    return keys;
  };

  // Retrieve the values of an object's properties.
  _.values = function(obj) {
    var keys = _.keys(obj);
    var length = keys.length;
    var values = Array(length);
    for (var i = 0; i < length; i++) {
      values[i] = obj[keys[i]];
    }
    return values;
  };

  // Convert an object into a list of `[key, value]` pairs.
  _.pairs = function(obj) {
    var keys = _.keys(obj);
    var length = keys.length;
    var pairs = Array(length);
    for (var i = 0; i < length; i++) {
      pairs[i] = [keys[i], obj[keys[i]]];
    }
    return pairs;
  };

  // Invert the keys and values of an object. The values must be serializable.
  _.invert = function(obj) {
    var result = {};
    var keys = _.keys(obj);
    for (var i = 0, length = keys.length; i < length; i++) {
      result[obj[keys[i]]] = keys[i];
    }
    return result;
  };

  // Return a sorted list of the function names available on the object.
  // Aliased as `methods`
  _.functions = _.methods = function(obj) {
    var names = [];
    for (var key in obj) {
      if (_.isFunction(obj[key])) names.push(key);
    }
    return names.sort();
  };

  // Extend a given object with all the properties in passed-in object(s).
  _.extend = function(obj) {
    if (!_.isObject(obj)) return obj;
    var source, prop;
    for (var i = 1, length = arguments.length; i < length; i++) {
      source = arguments[i];
      for (prop in source) {
        if (hasOwnProperty.call(source, prop)) {
            obj[prop] = source[prop];
        }
      }
    }
    return obj;
  };

  // Return a copy of the object only containing the whitelisted properties.
  _.pick = function(obj, iteratee, context) {
    var result = {}, key;
    if (obj == null) return result;
    if (_.isFunction(iteratee)) {
      iteratee = createCallback(iteratee, context);
      for (key in obj) {
        var value = obj[key];
        if (iteratee(value, key, obj)) result[key] = value;
      }
    } else {
      var keys = concat.apply([], slice.call(arguments, 1));
      obj = new Object(obj);
      for (var i = 0, length = keys.length; i < length; i++) {
        key = keys[i];
        if (key in obj) result[key] = obj[key];
      }
    }
    return result;
  };

   // Return a copy of the object without the blacklisted properties.
  _.omit = function(obj, iteratee, context) {
    if (_.isFunction(iteratee)) {
      iteratee = _.negate(iteratee);
    } else {
      var keys = _.map(concat.apply([], slice.call(arguments, 1)), String);
      iteratee = function(value, key) {
        return !_.contains(keys, key);
      };
    }
    return _.pick(obj, iteratee, context);
  };

  // Fill in a given object with default properties.
  _.defaults = function(obj) {
    if (!_.isObject(obj)) return obj;
    for (var i = 1, length = arguments.length; i < length; i++) {
      var source = arguments[i];
      for (var prop in source) {
        if (obj[prop] === void 0) obj[prop] = source[prop];
      }
    }
    return obj;
  };

  // Create a (shallow-cloned) duplicate of an object.
  _.clone = function(obj) {
    if (!_.isObject(obj)) return obj;
    return _.isArray(obj) ? obj.slice() : _.extend({}, obj);
  };

  // Invokes interceptor with the obj, and then returns obj.
  // The primary purpose of this method is to "tap into" a method chain, in
  // order to perform operations on intermediate results within the chain.
  _.tap = function(obj, interceptor) {
    interceptor(obj);
    return obj;
  };

  // Internal recursive comparison function for `isEqual`.
  var eq = function(a, b, aStack, bStack) {
    // Identical objects are equal. `0 === -0`, but they aren't identical.
    // See the [Harmony `egal` proposal](http://wiki.ecmascript.org/doku.php?id=harmony:egal).
    if (a === b) return a !== 0 || 1 / a === 1 / b;
    // A strict comparison is necessary because `null == undefined`.
    if (a == null || b == null) return a === b;
    // Unwrap any wrapped objects.
    if (a instanceof _) a = a._wrapped;
    if (b instanceof _) b = b._wrapped;
    // Compare `[[Class]]` names.
    var className = toString.call(a);
    if (className !== toString.call(b)) return false;
    switch (className) {
      // Strings, numbers, regular expressions, dates, and booleans are compared by value.
      case '[object RegExp]':
      // RegExps are coerced to strings for comparison (Note: '' + /a/i === '/a/i')
      case '[object String]':
        // Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
        // equivalent to `new String("5")`.
        return '' + a === '' + b;
      case '[object Number]':
        // `NaN`s are equivalent, but non-reflexive.
        // Object(NaN) is equivalent to NaN
        if (+a !== +a) return +b !== +b;
        // An `egal` comparison is performed for other numeric values.
        return +a === 0 ? 1 / +a === 1 / b : +a === +b;
      case '[object Date]':
      case '[object Boolean]':
        // Coerce dates and booleans to numeric primitive values. Dates are compared by their
        // millisecond representations. Note that invalid dates with millisecond representations
        // of `NaN` are not equivalent.
        return +a === +b;
    }
    if (typeof a != 'object' || typeof b != 'object') return false;
    // Assume equality for cyclic structures. The algorithm for detecting cyclic
    // structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
    var length = aStack.length;
    while (length--) {
      // Linear search. Performance is inversely proportional to the number of
      // unique nested structures.
      if (aStack[length] === a) return bStack[length] === b;
    }
    // Objects with different constructors are not equivalent, but `Object`s
    // from different frames are.
    var aCtor = a.constructor, bCtor = b.constructor;
    if (
      aCtor !== bCtor &&
      // Handle Object.create(x) cases
      'constructor' in a && 'constructor' in b &&
      !(_.isFunction(aCtor) && aCtor instanceof aCtor &&
        _.isFunction(bCtor) && bCtor instanceof bCtor)
    ) {
      return false;
    }
    // Add the first object to the stack of traversed objects.
    aStack.push(a);
    bStack.push(b);
    var size, result;
    // Recursively compare objects and arrays.
    if (className === '[object Array]') {
      // Compare array lengths to determine if a deep comparison is necessary.
      size = a.length;
      result = size === b.length;
      if (result) {
        // Deep compare the contents, ignoring non-numeric properties.
        while (size--) {
          if (!(result = eq(a[size], b[size], aStack, bStack))) break;
        }
      }
    } else {
      // Deep compare objects.
      var keys = _.keys(a), key;
      size = keys.length;
      // Ensure that both objects contain the same number of properties before comparing deep equality.
      result = _.keys(b).length === size;
      if (result) {
        while (size--) {
          // Deep compare each member
          key = keys[size];
          if (!(result = _.has(b, key) && eq(a[key], b[key], aStack, bStack))) break;
        }
      }
    }
    // Remove the first object from the stack of traversed objects.
    aStack.pop();
    bStack.pop();
    return result;
  };

  // Perform a deep comparison to check if two objects are equal.
  _.isEqual = function(a, b) {
    return eq(a, b, [], []);
  };

  // Is a given array, string, or object empty?
  // An "empty" object has no enumerable own-properties.
  _.isEmpty = function(obj) {
    if (obj == null) return true;
    if (_.isArray(obj) || _.isString(obj) || _.isArguments(obj)) return obj.length === 0;
    for (var key in obj) if (_.has(obj, key)) return false;
    return true;
  };

  // Is a given value a DOM element?
  _.isElement = function(obj) {
    return !!(obj && obj.nodeType === 1);
  };

  // Is a given value an array?
  // Delegates to ECMA5's native Array.isArray
  _.isArray = nativeIsArray || function(obj) {
    return toString.call(obj) === '[object Array]';
  };

  // Is a given variable an object?
  _.isObject = function(obj) {
    var type = typeof obj;
    return type === 'function' || type === 'object' && !!obj;
  };

  // Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp.
  _.each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp'], function(name) {
    _['is' + name] = function(obj) {
      return toString.call(obj) === '[object ' + name + ']';
    };
  });

  // Define a fallback version of the method in browsers (ahem, IE), where
  // there isn't any inspectable "Arguments" type.
  if (!_.isArguments(arguments)) {
    _.isArguments = function(obj) {
      return _.has(obj, 'callee');
    };
  }

  // Optimize `isFunction` if appropriate. Work around an IE 11 bug.
  if (typeof /./ !== 'function') {
    _.isFunction = function(obj) {
      return typeof obj == 'function' || false;
    };
  }

  // Is a given object a finite number?
  _.isFinite = function(obj) {
    return isFinite(obj) && !isNaN(parseFloat(obj));
  };

  // Is the given value `NaN`? (NaN is the only number which does not equal itself).
  _.isNaN = function(obj) {
    return _.isNumber(obj) && obj !== +obj;
  };

  // Is a given value a boolean?
  _.isBoolean = function(obj) {
    return obj === true || obj === false || toString.call(obj) === '[object Boolean]';
  };

  // Is a given value equal to null?
  _.isNull = function(obj) {
    return obj === null;
  };

  // Is a given variable undefined?
  _.isUndefined = function(obj) {
    return obj === void 0;
  };

  // Shortcut function for checking if an object has a given property directly
  // on itself (in other words, not on a prototype).
  _.has = function(obj, key) {
    return obj != null && hasOwnProperty.call(obj, key);
  };

  // Utility Functions
  // -----------------

  // Run Underscore.js in *noConflict* mode, returning the `_` variable to its
  // previous owner. Returns a reference to the Underscore object.
  _.noConflict = function() {
    root._ = previousUnderscore;
    return this;
  };

  // Keep the identity function around for default iteratees.
  _.identity = function(value) {
    return value;
  };

  _.constant = function(value) {
    return function() {
      return value;
    };
  };

  _.noop = function(){};

  _.property = function(key) {
    return function(obj) {
      return obj[key];
    };
  };

  // Returns a predicate for checking whether an object has a given set of `key:value` pairs.
  _.matches = function(attrs) {
    var pairs = _.pairs(attrs), length = pairs.length;
    return function(obj) {
      if (obj == null) return !length;
      obj = new Object(obj);
      for (var i = 0; i < length; i++) {
        var pair = pairs[i], key = pair[0];
        if (pair[1] !== obj[key] || !(key in obj)) return false;
      }
      return true;
    };
  };

  // Run a function **n** times.
  _.times = function(n, iteratee, context) {
    var accum = Array(Math.max(0, n));
    iteratee = createCallback(iteratee, context, 1);
    for (var i = 0; i < n; i++) accum[i] = iteratee(i);
    return accum;
  };

  // Return a random integer between min and max (inclusive).
  _.random = function(min, max) {
    if (max == null) {
      max = min;
      min = 0;
    }
    return min + Math.floor(Math.random() * (max - min + 1));
  };

  // A (possibly faster) way to get the current timestamp as an integer.
  _.now = Date.now || function() {
    return new Date().getTime();
  };

   // List of HTML entities for escaping.
  var escapeMap = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#x27;',
    '`': '&#x60;'
  };
  var unescapeMap = _.invert(escapeMap);

  // Functions for escaping and unescaping strings to/from HTML interpolation.
  var createEscaper = function(map) {
    var escaper = function(match) {
      return map[match];
    };
    // Regexes for identifying a key that needs to be escaped
    var source = '(?:' + _.keys(map).join('|') + ')';
    var testRegexp = RegExp(source);
    var replaceRegexp = RegExp(source, 'g');
    return function(string) {
      string = string == null ? '' : '' + string;
      return testRegexp.test(string) ? string.replace(replaceRegexp, escaper) : string;
    };
  };
  _.escape = createEscaper(escapeMap);
  _.unescape = createEscaper(unescapeMap);

  // If the value of the named `property` is a function then invoke it with the
  // `object` as context; otherwise, return it.
  _.result = function(object, property) {
    if (object == null) return void 0;
    var value = object[property];
    return _.isFunction(value) ? object[property]() : value;
  };

  // Generate a unique integer id (unique within the entire client session).
  // Useful for temporary DOM ids.
  var idCounter = 0;
  _.uniqueId = function(prefix) {
    var id = ++idCounter + '';
    return prefix ? prefix + id : id;
  };

  // By default, Underscore uses ERB-style template delimiters, change the
  // following template settings to use alternative delimiters.
  _.templateSettings = {
    evaluate    : /<%([\s\S]+?)%>/g,
    interpolate : /<%=([\s\S]+?)%>/g,
    escape      : /<%-([\s\S]+?)%>/g
  };

  // When customizing `templateSettings`, if you don't want to define an
  // interpolation, evaluation or escaping regex, we need one that is
  // guaranteed not to match.
  var noMatch = /(.)^/;

  // Certain characters need to be escaped so that they can be put into a
  // string literal.
  var escapes = {
    "'":      "'",
    '\\':     '\\',
    '\r':     'r',
    '\n':     'n',
    '\u2028': 'u2028',
    '\u2029': 'u2029'
  };

  var escaper = /\\|'|\r|\n|\u2028|\u2029/g;

  var escapeChar = function(match) {
    return '\\' + escapes[match];
  };

  // JavaScript micro-templating, similar to John Resig's implementation.
  // Underscore templating handles arbitrary delimiters, preserves whitespace,
  // and correctly escapes quotes within interpolated code.
  // NB: `oldSettings` only exists for backwards compatibility.
  _.template = function(text, settings, oldSettings) {
    if (!settings && oldSettings) settings = oldSettings;
    settings = _.defaults({}, settings, _.templateSettings);

    // Combine delimiters into one regular expression via alternation.
    var matcher = RegExp([
      (settings.escape || noMatch).source,
      (settings.interpolate || noMatch).source,
      (settings.evaluate || noMatch).source
    ].join('|') + '|$', 'g');

    // Compile the template source, escaping string literals appropriately.
    var index = 0;
    var source = "__p+='";
    text.replace(matcher, function(match, escape, interpolate, evaluate, offset) {
      source += text.slice(index, offset).replace(escaper, escapeChar);
      index = offset + match.length;

      if (escape) {
        source += "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'";
      } else if (interpolate) {
        source += "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'";
      } else if (evaluate) {
        source += "';\n" + evaluate + "\n__p+='";
      }

      // Adobe VMs need the match returned to produce the correct offest.
      return match;
    });
    source += "';\n";

    // If a variable is not specified, place data values in local scope.
    if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';

    source = "var __t,__p='',__j=Array.prototype.join," +
      "print=function(){__p+=__j.call(arguments,'');};\n" +
      source + 'return __p;\n';

    try {
      var render = new Function(settings.variable || 'obj', '_', source);
    } catch (e) {
      e.source = source;
      throw e;
    }

    var template = function(data) {
      return render.call(this, data, _);
    };

    // Provide the compiled source as a convenience for precompilation.
    var argument = settings.variable || 'obj';
    template.source = 'function(' + argument + '){\n' + source + '}';

    return template;
  };

  // Add a "chain" function. Start chaining a wrapped Underscore object.
  _.chain = function(obj) {
    var instance = _(obj);
    instance._chain = true;
    return instance;
  };

  // OOP
  // ---------------
  // If Underscore is called as a function, it returns a wrapped object that
  // can be used OO-style. This wrapper holds altered versions of all the
  // underscore functions. Wrapped objects may be chained.

  // Helper function to continue chaining intermediate results.
  var result = function(obj) {
    return this._chain ? _(obj).chain() : obj;
  };

  // Add your own custom functions to the Underscore object.
  _.mixin = function(obj) {
    _.each(_.functions(obj), function(name) {
      var func = _[name] = obj[name];
      _.prototype[name] = function() {
        var args = [this._wrapped];
        push.apply(args, arguments);
        return result.call(this, func.apply(_, args));
      };
    });
  };

  // Add all of the Underscore functions to the wrapper object.
  _.mixin(_);

  // Add all mutator Array functions to the wrapper.
  _.each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) {
    var method = ArrayProto[name];
    _.prototype[name] = function() {
      var obj = this._wrapped;
      method.apply(obj, arguments);
      if ((name === 'shift' || name === 'splice') && obj.length === 0) delete obj[0];
      return result.call(this, obj);
    };
  });

  // Add all accessor Array functions to the wrapper.
  _.each(['concat', 'join', 'slice'], function(name) {
    var method = ArrayProto[name];
    _.prototype[name] = function() {
      return result.call(this, method.apply(this._wrapped, arguments));
    };
  });

  // Extracts the result from a wrapped and chained object.
  _.prototype.value = function() {
    return this._wrapped;
  };

  // AMD registration happens at the end for compatibility with AMD loaders
  // that may not enforce next-turn semantics on modules. Even though general
  // practice for AMD registration is to be anonymous, underscore registers
  // as a named module because, like jQuery, it is a base library that is
  // popular enough to be bundled in a third party lib, but not be part of
  // an AMD load request. Those cases could generate an error when an
  // anonymous define() is called outside of a loader request.
  if (typeof define === 'function' && define.amd) {
    define('underscore', [], function() {
      return _;
    });
  }
}.call(this));

//// END OF THE underscore.js SOURCE CODE


(function(global, _) {
  'use strict';
  _ = _.noConflict();

  var underscoreKeys = _.keys(_);

    /**
     * This will be the <code>warmsea</code> namespace.
     * @namespace
     * @alias warmsea
     */
    var w = _.extend({}, _);

    /**
     * The unmodified underlying underscore object.
     */
    w._ = w.underscore = _;

    /**
     * The version of this WarmseaJS.
     * @type {string}
     */
    w.VERSION = '1.0.0';

    /**
     * The global object of the executing environment.
     * @type {object}
     */
    w.global = global;

    /**
     * Save the previous `warmsea`.
     */
    var previousWarmsea = global.warmsea;

    /**
     * Return the current `warmsea` and restore the previous global one.
     * @return {warmsea} This warmsea object.
     */
    w.noConflict = function() {
      global.warmsea = previousWarmsea;
      return this;
    };

    /**
     * A function that throws an error with the message "Unimplemented".
     */
    w.unimplemented = function() {
      w.error('Unimplemented');
    };

    /**
     * Throws an Error.
     * @method
     * @param {string} msg
     * @throws {Error}
     */
    w.error = function(msg) {
      if (w.isFunction(w.format)) {
        msg = w.format.apply(w, arguments);
      }
      throw new Error(msg);
    };

  /**
   * A compare function returns 1, if a &lt; b; -1, if a &gt; b; 0, otherwise.
   * @param {any} a
   * @param {any} b
   * @return {number}
   */
  w.cmp = function(a, b) {
    return a > b ? 1 : a < b ? -1 : 0;
  };

  /**
   * Tests if an item is in an array.
   *
   * @param {Array} arr The array
   * @param {*} item The item
   * @returns {Boolean} true, if the item is in the array; false, if not.
   */
  w.inArray = function(arr, item) {
    if (!w.isArray(arr)) {
      return false;
    }
    return w.indexOf(arr, item) >= 0;
  };

  /**
   * In-place stable sort.
   *
   * @param {Array} list The array to be sorted.
   * @param {Function} cmp The compare function; by default, it's w.cmp。
   * @param {Object} context The context for cmp.
   * @returns {Array} The sorted array.
   */
  w.sort = function(list, cmp, context) {
    cmp = cmp || w.cmp;
    var i;
    var len = list.length;
    for (i = 0; i < len; ++i) {
      // _$wssi stands for Warmsea Stable Sort Id
      // I hope no one is using it.
      list[i]._$wssi = i;
    }
    list.sort(function(a, b) {
      return cmp.call(context, a, b) || w.cmp(a._$wssi - b._$wssi);
    });
    for (i = 0; i < len; ++i) {
      delete list[i]._$wssi;
    }
    return list;
  };

  /**
   * Returns a (stably) sorted (shallow) copy of an array.
   *
   * @param {Array} list The array to be sorted.
   * @param {Function} cmp The compare function; by default, it's w.cmp.
   * @param {Object} context The context for cmp.
   * @returns {Array} A sorted copy.
   */
  w.sorted = function(list, cmp, context) {
    var copy = w.clone(list);
    w.sort(copy, cmp, context);
    return copy;
  };

  w.Queue = (function() {

    /**
     * Queue class. A Queue is a FIFO (First In, First Out) collection.
     *
     * @class
     * @name warmsea.Queue
     * @param {?function} validator A value validation function.
     */
    var Queue = function(validator) {
      this._validator = validator;
      this.clear();
      this.allowEmptyDequeue = true;
    };

    /**
     * Returns number of elements in the Queue.
     *
     * @return {number}
     */
    Queue.prototype.count = function() {
      return this._queue.length - this._offset;
    };

    /**
     * Number of elements in the Queue.
     * @type {number}
     */
    if (w.isFunction(Object.defineProperty)) {
      // I'm not interested in fully supporting IE 8.
      // But I don't want it dies in the first place.
      Object.defineProperty(Queue.prototype, 'length', {
        enumerable: true,
        get: function() {
          return this.count();
        }
      });
    }

    /**
     * Remove all objects from the Queue.
     *
     * @method
     * @name warmsea.Queue.prototype.clear
     */
    Queue.prototype.clear = function() {
      this._queue = [];
      this._offset = 0;
    };

    /**
     * Add an object to the end of the Queue.
     *
     * @method
     * @name warmsea.Queue.prototype.enqueue
     * @param {Object} value An object.
     * @throws {Error} If value can't pass the validation.
     */
    Queue.prototype.enqueue = function(value) {
      if (this._validator && !this._validator(value)) {
        w.error('Value not accepted: ' + value);
      }
      this._queue.push(value);
    };

    /**
     * Remove the object at the beginning of the Queue and return it.
     *
     * @method
     * @name warmsea.Queue.prototype.dequeue
     * @return {any} The object at the beginning of the Queue.
     */
    Queue.prototype.dequeue = function() {
      if (this.length === 0) {
        if (this.allowEmptyDequeue) {
          return undefined;
        } else {
          w.error('The queue is empty');
        }
      }
      var item = this._queue[this._offset++];
      if (this._offset > 16 && this._offset * 2 > this._queue.length) {
        this._queue = this._queue.slice(this._offset);
        this._offset = 0;
      }
      return item;
    };

    /**
     * Return the object at the beginning of the Queue without removing it.
     *
     * @method
     * @name warmsea.Queue.prototype.peek
     * @return {any} The object at the beginning of the Queue.
     */
    Queue.prototype.peek = function() {
      if (this.length === 0) {
        if (this.allowEmptyDequeue) {
          return undefined;
        } else {
          w.error('Dequeueing an empty queue is not allowed');
        }
      }
      return this._queue[this._offset];
    };

    return Queue;

  })();

  w.Stack = (function() {

    /**
     * Stack class. A Stack is a FILO (First In, Last Out) collection.
     *
     * @class
     * @name warmsea.Stack
     * @param {?function} validator A value validation function.
     */
    var Stack = function(validator) {
      this._validator = validator;
      this.clear();
      this.allowEmptyPop = true;
    };

    /**
     * Returns number of elements in the Stack.
     *
     * @return {number}
     */
    Stack.prototype.count = function() {
      return this._top + 1;
    };

    /**
     * Number of elements in the Queue.
     * @type {number}
     */
    if (w.isFunction(Object.defineProperty)) {
      // I'm not interested in fully supporting IE 8.
      // But I don't want it dies in the first place.
      Object.defineProperty(Stack.prototype, 'length', {
        enumerable: true,
        get: function() {
          return this.count();
        }
      });
    }

    /**
     * Remove all objects from the Stack.
     *
     * @method
     * @name warmsea.Stack.prototype.clear
     */
    Stack.prototype.clear = function() {
      this._stack = [];
      this._top = -1;
    };

    /**
     * Add an object to the top of the Stack.
     *
     * @method
     * @name warmsea.Stack.prototype.push
     * @param {Object} value An object.
     * @throws {Error} If value can't pass the validation.
     */
    Stack.prototype.push = function(value) {
      if (this._validator && !this._validator(value)) {
        w.error('Value not accepted: ' + value);
      }
      this._top++;
      if (this._top < this.length) {
        this._stack[this._top] = value;
      } else {
        this._stack.push(value);
      }
    };

    /**
     * Remove the object at the top of the Stack and return it.
     *
     * @method
     * @name warmsea.Stack.prototype.pop
     * @return {any} The object at the top of the Stack.
     */
    Stack.prototype.pop = function() {
      if (this.length === 0) {
        if (this.allowEmptyPop) {
          return undefined;
        } else {
          w.error('The stack is empty');
        }
      }
      var item = this._stack[this._top--];
      if (this._top > 16 && this._top * 2 < this._stack.length) {
        this._stack = this._stack.slice(0, this._top + 1);
      }
      return item;
    };

    /**
     * Return the object at the top of the Stack without removing it.
     *
     * @method
     * @name warmsea.Stack.prototype.peek
     * @return {any} The object at the top of the Stack.
     */
    Stack.prototype.peek = function() {
      if (this.length === 0) {
        if (this.allowEmptyPop) {
          return undefined;
        } else {
          w.error('Popping an empty stack is not allowed');
        }
      }
      return this._stack[this._top];
    };

    return Stack;

  })();


  /**
   * Convert an arbitrary value to a boolean value.
   * @param {any} value
   * @return {boolean}
   */
  w.bool = function(value) {
    var v = value;
    if (w.isObject(v) && '__bool__' in v) {
      return w.bool(w.isFunction(v.__bool__) ? v.__bool__() : v.__bool__);
    } else {
      return !!value;
    }
  };

  /**
   * Convert a value to an Integer.
   * @param {any} value
   * @param {number} radix An integer between 2 and 32.
   * @return {number}
   */
  w.i = function(value, radix) {
    var v = value;
    if (v === false) {
      return 0;
    } else if (v === true) {
      return 1;
    } else if (w.isObject(v) && '__int__' in v) {
      return w.i(w.isFunction(v.__int__) ? v.__int__() : v.__int__, radix);
    } else if (!radix && w.isString(v) && (v.indexOf('0x') === 0 || v.indexOf('0X') === 0)) {
      return parseInt(v, 16);
    } else if (!radix || radix === 10) {
      return Math.round(parseFloat(v));
    } else {
      return parseInt(v, radix);
    }
  };

  /**
   * Convert a value to a number.
   * @param {any} valueq
   * @return {number}
   */
  w.f = function(value) {
    var v = value;
    if (v === false) {
      return 0.0;
    } else if (v === true) {
      return 1.0;
    } else if (w.isObject(v) && '__float__' in v) {
      return w.f(w.isFunction(v.__float__) ? v.__float__() : v.__float__);
    } else {
      return parseFloat(v);
    }
  };

  /**
   * Convert a value to a String.
   * @param {any} value
   * @return {string}
   */
  w.str = function(value) {
    var v = value;
    if (w.isObject(v) && '__str__' in v) {
      return w.str(w.isFunction(v.__str__) ? v.__str__() : v.__str__);
    } else {
      return String(value);
    }
  };

  /**
   * Convert a value to an array.
   * @param {any} value
   * @return {Array}
   */
  w.array = function(value) {
    if (w.isArray(value)) {
      return value;
    } else if (value === undefined || value === null) {
      return [];
    } else {
      return [value];
    }
  };

  /**
   * Test whether a value is an safe integer.
   * <p>
   * JavaScript has only one number type, that is 64-bit floating-point number. So we test whether the value is an
   * integer in that system. Which means 1.0 and 1 are both integers, but 9007199254740994 is not an integer because it
   * exceeds the max/min safe integer value a 64-bit floating-point number can present.
   * @param {any} value
   * @return {boolean}
   */
  w.isInt = function(value) {
    // return w.isNumber(value) && value % 1 === 0 &&
    // value >= Number.MIN_SAFE_INTEGER && value <= Number.MAX_SAFE_INTEGER;
    return w.isNumber(value) && value % 1 === 0 && value >= -9007199254740991 && value <= 9007199254740991;
  };

  /**
   * Test whether a value is a plain object.
   * <p>
   * ATTENSION: I'm not pretty sure whether this function works everywhere. Can anyone help me?
   * <p>
   * A plain object is typically an object defined with <code>{}</code> or <code>new Object</code>.
   *
   * @param {any} value
   * @return {boolean}
   */
  w.isPlainObject = function(value) {
    if (!w.isObject(value)) {
      return false;
    }
    try {
      if (!value.constructor.prototype.hasOwnProperty('isPrototypeOf')) {
        return false;
      }
    } catch (e) {
      return false;
    }
    return true;
  };

  /**
   * Pad a string to a given length by adding leading characters.
   * @method
   * @param {number|string} value The value; it can be a number.
   * @param {int} length The wanted length. Defaults to 2.
   * @param {string} leading The leading character. Defaults to a space (' ').
   */
  w.pad = function(value, length, leading) {
    value = w.str(value);
    length = w.max([0, length === undefined ? 0 : length, value.length]);
    leading = w.str(leading === undefined ? ' ' : leading);
    var a = new Array(Math.ceil((length - value.length) / leading.length) + 1);
    return a.join(leading).substring(0, length - value.length) + value;
  };

  /**
   * Replace each conversion specifier of a format string with the string
   * representation of a specified object.
   * @method
   * @param {string|function} format the format string.
   * @param {...any|any[]|PlainObject} args Arguments one by one, or a list,
   *    or a map.
   * @return {string} The formatted string.
   */
  w.format = (function(w) {

    var f = function(format /* , args_array | args_map | arg1, arg2,  ... */) {
      if (!arguments.length) {
        return '';
      }
      format = func2str(arguments[0]);

      var params;
      if (w.isArray(arguments[1])) {
        params = arguments[1];
      } else if (w.isPlainObject(arguments[1])) {
        params = arguments[1];
      } else {
        params = Array.prototype.slice.call(arguments, 1);
      }

      var converter = new FormatConverter(params);

      var specifiers = /%(?:\((.*?)\))?([#|0|\-| |\+]+)?(\d+|\*)?(?:.(\d+|\*))?(?:[h|l|L])?(.)?/g;

      format = format.replace(specifiers, function() {
        return FormatConverter.prototype.convert.apply(converter, arguments);
      });

      return format;
    };

    /**
     * Convert a function into a (multi-line) string.
     * @method
     * @param {function} func
     * @return {string}
     */
    var func2str = function(func) {
      if (w.isString(func)) {
        return func;
      } else if (!w.isFunction(func)) {
        return w.str(func);
      }

      var lines = w.str(func).split(/\r?\n/);
      var i = 0, j = 0, len = lines.length;
      var startIndex, endIndex;
      var endTag, options = {};
      var dent = null;

      // Find the start line.
      while (i < len) {
        var start = lines[i++].match(/^[ \t]*\/\*\*?!?<<<(\w+)(?:;(.+)?)?$/);
        if (!start) {
          continue;
        }
        startIndex = i;
        endTag = start[1];
        var optionTags = (start[2] || '').split(/[ \t]*,[ \t]*/);
        for (j = 0; j < optionTags.length; ++j) {
          var tag = optionTags[j].toLowerCase().split(/-(.*)/);
          if (tag[0]) {
            options[tag[0]] = tag[1] || true;
          }
        }
        break;
      }
      if (!startIndex) {
        w.error('Format failed: start line missing');
      }

      // The default WS option is "OUTDENT".
      options.ws = options.ws || 'outdent';

      var result = [];

      // Find the end line.
      while (i < len) {
        var line = lines[i];
        if (line.match(new RegExp('^[ \\t]*' + endTag + '\\*\\/'))) {
          endIndex = i;
          break;
        }
        i++;
        // Count the dent here.
        if (options.ws === 'outdent') {
          var match = line.match(/^([ \t]*).*$/);
          var cur = match[1];
          if (dent === null) {
            dent = cur;
          } else {
            j = 0;
            while (j < dent.length && j < cur.length && dent[j] === cur[j]) {
              j++;
            }
            if (dent.length > j) {
              dent = dent.substring(0, j);
            }
          }
        }
        result.push(line);
      }
      if (!endIndex) {
        w.error('Format failed: end line missing');
      }

      var wsFunc;
      switch (options.ws) {
        case 'outdent':
          wsFunc = function(s) {
            return s.substring(dent.length);
          };
          break;
        case 'keep':
          wsFunc = w.identity;
          break;
        case 'trim':
          wsFunc = function(s) {
            return s.trim();
          };
          break;
        default:
          w.error('Format failed: Unsupported WS option');
      }

      for (i = 0, len = result.length; i < len; ++i) {
        result[i] = wsFunc(result[i]);
      }

      return result.join('\n');
    };

    /**
     * Converter for <code>warmsea.format()</code> function.
     * @class
     * @param {string[]} params
     */
    var FormatConverter = function(params) {
      this.params = params || [];
      this.index = 0;
    };

    /**
     * Convert a specifier to wanted string.
     * @method
     * @param {string} specifier
     * @param {string} key
     * @param {string} flags
     * @param {string} width
     * @param {string} precision
     * @param {string} type
     * @param {string} position
     */
    FormatConverter.prototype.convert = function(specifier, key, flags, width, precision, type, position) {
      if (type === undefined) {
        w.error('format incomplete specifier "%s" in position (%d).', specifier, position);
      }
      if (!this.convertors.hasOwnProperty(type)) {
        w.error('format unsupported type "%s" in position (%d)', type, position);
      }

      var next;

      if (width === '*') {
        next = this.index++;
        if (!this.params.hasOwnProperty(next)) {
          w.error('format key error "%s" in position (%d).', key, position);
        }
        width = this.params[next];
      }
      width = width || 0;

      if (precision === '*') {
        next = this.index++;
        if (!this.params.hasOwnProperty(next)) {
          w.error('format key error "%s" in position (%d).', key, position);
        }
        precision = this.params[next];
      }
      if (precision === undefined) {
        precision = 6;
      }

      if (type === '%' || type === '/') {
        return type;
      }

      key = key === undefined ? this.index++ : key;
      if (!this.params.hasOwnProperty(key)) {
        w.error('format key error "%s" in position (%d).', key, position);
      }
      var value = this.params[key];

      flags = flags || '';
      flags = {
        '#': flags.indexOf('#') >= 0,
        '0': flags.indexOf('0') >= 0 && flags.indexOf('-') < 0,
        '-': flags.indexOf('-') >= 0,
        ' ': flags.indexOf(' ') >= 0 && flags.indexOf('+') < 0,
        '+': flags.indexOf('+') >= 0
      };

      return this.convertors[type](value, flags, width, precision);
    };

    /**
     * The converters of each type.
     */
    FormatConverter.prototype.convertors = {
      'd': function(value, flags, width /*, precision */) {
        return FormatConverter.prototype.convertors.ic('d', value, flags, width);
      },
      'o': function(value, flags, width /*, precision */) {
        return FormatConverter.prototype.convertors.ic('o', value, flags, width);
      },
      'x': function(value, flags, width /*, precision */) {
        return FormatConverter.prototype.convertors.ic('x', value, flags, width);
      },
      'X': function(value, flags, width /*, precision */) {
        return FormatConverter.prototype.convertors.ic('X', value, flags, width);
      },
      'f': function(value, flags, width, precision) {
        value = w.f(value);
        var sign = value < 0 ? '-' : (flags['+'] ? '+' : flags[' '] ? ' ' : '');
        value = Math.abs(value).toFixed(precision);
        if (flags['#'] && precision === 0) {
          value += '.';
        }
        var gap = w.max([0, width - value.length - sign.length]);
        if (flags['-']) {
          return sign + value + w.pad('', gap, ' ');
        } else if (flags['0']) {
          return sign + w.pad('', gap, '0') + value;
        } else {
          return w.pad('', gap, ' ') + sign + value;
        }
      },
      's': function(value, flags, width /*, precision */) {
        value = w.str(value);
        var gap = w.max([0, width - value.length]);
        if (flags['-']) {
          return value + w.pad('', gap, ' ');
        } else {
          return w.pad('', gap, ' ') + value;
        }
      },
      '%': function() {
        this.index--;
        return '%';
      },
      '/': function() {
        this.index--;
        return '/';
      },
      'ic': function(type, value, flags, width) {
        value = w.i(value);
        var sign = value < 0 ? '-' : (flags['+'] ? '+' : flags[' '] ? ' ' : '');
        var prefix = flags['#'] ? {
          'd': '',
          'o': '0',
          'x': '0x',
          'X': '0X'
        }[type] : '';
        value = Math.abs(value).toString({
          'd': 10,
          'o': 8,
          'x': 16,
          'X': 16
        }[type]);
        var gap = w.max([0, width - prefix.length - value.length - sign.length]);
        var result = '';
        if (flags['-']) {
          result = sign + prefix + value + w.pad('', gap, ' ');
        } else if (flags['0']) {
          result = sign + prefix + w.pad('', gap, '0') + value;
        } else {
          result = w.pad('', gap, ' ') + sign + prefix + value;
        }
        if (type === 'X') {
          result = result.toUpperCase();
        }
        return result;
      }
    };

    return f;

  })(w);


  /**
   * Create a debugger function with a name.
   * @method
   * @param {string} name
   * @return {function}
   */
  w.debug = (function() {

    /**
     * Hold all the debuggers.
     * @type {object}
     */
    var debuggers = {};

    /**
     * Hold the enable status for all debuggers.
     * @type {object}
     */
    var enableStatus = {};

    /**
     * Debug modes.
     * @type {string[]}
     */
    var modes = [];

    /**
     * RegExp matchers for debug modes.
     * @type {object}
     */
    var modeMatchers = {};

    /**
     * Themes for styled logging.
     * @type {object}
     */
    var themes = {
      'tomorrow': [
        'color:#8e908c',  // The first style is for message.
        'color:#f5871f',  // Others for debugger name and time.
        'color:#8959a8',
        'color:#4271ae',
        'color:#718c00',
        'color:#eab700',
        'color:#c82829'
      ]
    };

    /**
     * Styles for styled logging.
     * @type {Array}
     */
    var styles = themes.tomorrow;

    /**
     * Current color position.
     * @type {number}
     */
    var pStyle = 0;

    /**
     * Detect Chrome browser.
     * Enable color for Chrome browser.
     * @type {boolean}
     */
    var isChrome = w.global.navigator && w.global.navigator.userAgent.toLowerCase().indexOf('chrome') !== -1;

    /**
     * Create a debugger function with a name.
     * @param {string} name
     * @return {function}
     */
    var debug = function(name) {
      if (debuggers[name]) {
        return debuggers[name];
      }
      var dbg = function(fmt) {
        // if this debugger is not enabled, do nothing.
        // Check it every time so we can enable or disable a debugger at runtime.
        // It won't be slow.
        if (!enableStatus[this._name]) {
          return;
        }

        fmt = coerce.apply(this, arguments);

        var curr = +new Date();  // IE8 don't have `Date.now()`
        var ms = curr - (this._timestamp || curr);
        this._timestamp = curr;

        if (isChrome) {
          fmt = '%c' + name + '%c ' + fmt + ' %c+' + humanize(ms);
          w.global.console.log(fmt, this._style, this._msgStyle, this._style);
        } else {
          fmt = name + ' ' + fmt + ' +' + humanize(ms);
          if (w.global.console && w.global.console.log) {
            w.global.console.log(fmt);
          }
          // Any one want to alert debug message? I think it's annoying.
        }
      };
      dbg._name = name;
      dbg._msgStyle = styles[0];
      dbg._style = style();
      enableStatus[name] = debug.enabled(name);
      debuggers[name] = dbg.bind(dbg);
      return debuggers[name];
    };

    /**
     * Coerce `fmt`.
     */
    var coerce = function(fmt) {
      if (fmt instanceof Error) {
        return fmt.stack || fmt.message;
      } else {
        return w.format.apply(this, arguments);
      }
    };

    /**
     * Get a style for styled logging.
     */
    var style = function() {
      return styles[pStyle++ % (styles.length - 1) + 1];
    };

    /**
     * Humanize the given milliseconds.
     * @param {number} ms number of milliseconds.
     * @return {string} A human readable representation.
     */
    var humanize = function(ms) {
      var sec = 1000;
      var min = 60 * 1000;
      var hour = 60 * min;

      if (ms >= hour) {
        return (ms / hour).toFixed(1) + 'h';
      }
      if (ms >= min) {
        return (ms / min).toFixed(1) + 'm';
      }
      if (ms >= sec) {
        return (ms / sec | 0) + 's';
      }
      return ms + 'ms';
    };

    /**
     * Enable debugger(s) with the specified name.
     * @param {string} name
     */
    debug.enable = function(name) {
      w.each((name || '').split(/[\s,]+/), function(mode) {
        if (mode[0] !== '+' && mode[0] !== '-') {
          mode = '+' + mode;
        }
        if (!modeMatchers[mode]) {
          modeMatchers[mode] = new RegExp('^' + mode.substring(1).replace('*', '.*') + '$');
        }
        var newModes = [];
        for (var i = 0, len = modes.length; i < len; ++i) {
          var m = modes[i];
          if ((m === mode) || (m.indexOf('*') < 0 && m.match(modeMatchers[mode]))) {
            continue;
          }
          newModes.push(m);
        }
        modes = newModes;
        modes.push(mode);
      });
      refreshEnableStatus();
    };

    /**
     * Enable debugger(s) with the specified name.
     * Call this function without an argument to disable all debug modes.
     * @param {?string} name
     */
    debug.disable = function(name) {
      if (name === undefined) {
        modes = [];
        modeMatchers = {};
      } else {
        var enableName = '';
        w.each(name.split(/[\s,]+/), function(n) {
          if (n[0] === '+' || n[1] === '-') {
            n = n.substring(1);
          }
          enableName += ', -' + n;
        });
        enableName = enableName.substring(2);
        debug.enable(enableName);
      }
      refreshEnableStatus();
    };

    /**
     * Return true if the given mode name is enabled, false otherwise.
     * @param {string} name
     * @return {boolean}
     */
    debug.enabled = function(name) {
      for (var i = modes.length - 1; i >= 0; --i) {
        if (name.match(modeMatchers[modes[i]])) {
          return modes[i][0] === '+';
        }
      }
      return false;
    };

    /**
     * Reset the enable status of all debuggers.
     */
    var refreshEnableStatus = function() {
      for (var name in debuggers) {
        enableStatus[name] = debug.enabled(name);
      }
    };

    return debug;

  })();

  /**
   * Deep copy a value (to a target).
   * @param {any} value
   * @param {?any} target
   * @return {any} the copied value.
   */
  w.deepcopy = function(value, target) {
    if (w.isArray(value)) {
      target = value.slice();
    } else if (w.isPlainObject(value)) {
      target = target || {};
      for (var i in value) {
        if (value.hasOwnProperty(i)) {
          target[i] = w.deepcopy(value[i], target[i]);
        }
      }
    } else {
      target = value;
    }
    return target;
  };

  /**
   * Hide specified properties of an object.
   * @param {Object} obj the object
   * @param {Array<String>} props names of the properties
   */
  w.hideProperties = function(obj, props) {
    if (!w.isFunction(Object.defineProperty)) {
      return;
    }

    w.each(props, function(key) {
      Object.defineProperty(obj, key, {
        enumerable: false,
        writable: true,
        configurable: true
      });
    });
  };

  /**
   * Add a memoized property to an object.
   * @param {Object} obj the object
   * @param {String} name name of the property
   * @param {Function} getter getter function of the property
   * @param {Boolean} enumerable whether the property if enumerable
   */
  w.memoizedProperty = function(obj, name, getter, enumerable) {
    if (!w.isFunction(Object.defineProperty)) {
      obj[name] = getter();
    }
    var cachedValue = null;

    Object.defineProperty(obj, name, {
      get: function() {
        if (cachedValue === null) {
          cachedValue = getter();
        }
        return cachedValue;
      },
      enumerable: enumerable
    });
  };

  /**
   * Return a random integer in the range of [start, end).
   * If end is not passed, the range will be [0, start).
   * @param {number} start
   * @param {number} end
   * @return {number}
   */
  w.randomInt = function(start, end) {
    if (start === undefined && end === undefined) {
      return 0;
    } else if (end === undefined) {
      end = start;
      start = 0;
    }
    start = Math.ceil(start);
    end = Math.ceil(end);
    if (start < end) {
      return start + Math.floor((end - start) * Math.random());
    } else if (start > end) {
      return start - Math.floor((start - end) * Math.random());
    } else {
      return NaN;
    }
  };

  /**
   * Choose a random floating-point number in the range of [start, end).
   * <p>
   * If end is not passed, the range will be [0, start).
   *
   * @param {number} start start of the range.
   * @param {number} end end of the range.
   * @return {number} A random number in the range.
   */
  w.randomFloat = function(start, end) {
    if (start === undefined && end === undefined) {
      return Math.random();
    } else if (end === undefined) {
      return Math.random() * start;
    } else if (start < end) {
      return start + Math.random() * (end - start);
    } else if (start > end) {
      return start - Math.random() * (start - end);
    } else {
      return NaN;
    }
  };

  /**
   * Return a random string.
   * @param {number} length Default to 8.
   * @param {string} allowedChars Default to "abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789"
   */
  w.randomString = function(length, allowedChars) {
    if (length === undefined) {
      length = 8;
    } else {
      length = w.i(length);
      length = w.max([length, 0]);
    }
    if (allowedChars === undefined) {
      allowedChars = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789';
    } else {
      allowedChars = w.str(allowedChars);
    }
    var res = '';
    var len = allowedChars.length;

    if (!len) {
      return '';
    }

    for (var i = 0; i < length; i++) {
      res += allowedChars[Math.floor(Math.random() * len)];
    }
    return res;
  };


  if (typeof exports !== 'undefined') {
    if (typeof module !== 'undefined' && module.exports) {
      exports = module.exports = w;
    } else {
      exports.warmsea = w;
    }
  } else if ( typeof define === 'function' && define.amd) {
    define(function() {
      return w;
    });
  } else {
    global.warmsea = w;
  }

  var compatibleKeys = ['VERSION', 'noConflict'];
  var overwritten = [];
  _.each(underscoreKeys, function(k) {
    if (_[k] !== w[k] && !w.inArray(compatibleKeys, k)) {
      overwritten.push(k);
    }
  });
  if (overwritten.length) {
    var overwritenMsg = 'The following functions of WarmseaJS ' +
        'is not fully compatible with underscore.js: ';
    overwritenMsg += '"' + overwritten.join('", "') + '"';
    if (global.console) {
      var warn = global.console.warn || global.console.log || w.noop;
      warn.call(global.console, overwritenMsg);
    }
  }

})(this, typeof exports !== 'undefined' ? exports._ : _);