Bump to v3.0.0.

function/after.js

@@ -0,0 +1,51 @@
+import isFunction from '../lang/isFunction';
+import root from '../internal/root';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/* Native method references for those with the same name as other `lodash` methods. */
+var nativeIsFinite = root.isFinite;
+
+/**
+ * The opposite of `_.before`; this method creates a function that invokes
+ * `func` once it is called `n` or more times.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {number} n The number of calls before `func` is invoked.
+ * @param {Function} func The function to restrict.
+ * @returns {Function} Returns the new restricted function.
+ * @example
+ *
+ * var saves = ['profile', 'settings'];
+ *
+ * var done = _.after(saves.length, function() {
+ *   console.log('done saving!');
+ * });
+ *
+ * _.forEach(saves, function(type) {
+ *   asyncSave({ 'type': type, 'complete': done });
+ * });
+ * // => logs 'done saving!' after the two async saves have completed
+ */
+function after(n, func) {
+  if (!isFunction(func)) {
+    if (isFunction(n)) {
+      var temp = n;
+      n = func;
+      func = temp;
+    } else {
+      throw new TypeError(FUNC_ERROR_TEXT);
+    }
+  }
+  n = nativeIsFinite(n = +n) ? n : 0;
+  return function() {
+    if (--n < 1) {
+      return func.apply(this, arguments);
+    }
+  };
+}
+
+export default after;

function/ary.js

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+import createWrapper from '../internal/createWrapper';
+import isIterateeCall from '../internal/isIterateeCall';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var ARY_FLAG = 256;
+
+/* Native method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
+
+/**
+ * Creates a function that accepts up to `n` arguments ignoring any
+ * additional arguments.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to cap arguments for.
+ * @param {number} [n=func.length] The arity cap.
+ * @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * _.map(['6', '8', '10'], _.ary(parseInt, 1));
+ * // => [6, 8, 10]
+ */
+function ary(func, n, guard) {
+  if (guard && isIterateeCall(func, n, guard)) {
+    n = null;
+  }
+  n = (func && n == null) ? func.length : nativeMax(+n || 0, 0);
+  return createWrapper(func, ARY_FLAG, null, null, null, null, n);
+}
+
+export default ary;

function/backflow.js

@@ -0,0 +1,2 @@
+import flowRight from './flowRight'
+export default flowRight;

function/before.js

@@ -0,0 +1,43 @@
+import isFunction from '../lang/isFunction';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/**
+ * Creates a function that invokes `func`, with the `this` binding and arguments
+ * of the created function, while it is called less than `n` times. Subsequent
+ * calls to the created function return the result of the last `func` invocation.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {number} n The number of calls at which `func` is no longer invoked.
+ * @param {Function} func The function to restrict.
+ * @returns {Function} Returns the new restricted function.
+ * @example
+ *
+ * jQuery('#add').on('click', _.before(5, addContactToList));
+ * // => allows adding up to 4 contacts to the list
+ */
+function before(n, func) {
+  var result;
+  if (!isFunction(func)) {
+    if (isFunction(n)) {
+      var temp = n;
+      n = func;
+      func = temp;
+    } else {
+      throw new TypeError(FUNC_ERROR_TEXT);
+    }
+  }
+  return function() {
+    if (--n > 0) {
+      result = func.apply(this, arguments);
+    } else {
+      func = null;
+    }
+    return result;
+  };
+}
+
+export default before;

function/bind.js

@@ -0,0 +1,58 @@
+import baseSlice from '../internal/baseSlice';
+import createWrapper from '../internal/createWrapper';
+import replaceHolders from '../internal/replaceHolders';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var BIND_FLAG = 1,
+    PARTIAL_FLAG = 32;
+
+/**
+ * Creates a function that invokes `func` with the `this` binding of `thisArg`
+ * and prepends any additional `_.bind` arguments to those provided to the
+ * bound function.
+ *
+ * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds,
+ * may be used as a placeholder for partially applied arguments.
+ *
+ * **Note:** Unlike native `Function#bind` this method does not set the `length`
+ * property of bound functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to bind.
+ * @param {*} thisArg The `this` binding of `func`.
+ * @param {...*} [args] The arguments to be partially applied.
+ * @returns {Function} Returns the new bound function.
+ * @example
+ *
+ * var greet = function(greeting, punctuation) {
+ *   return greeting + ' ' + this.user + punctuation;
+ * };
+ *
+ * var object = { 'user': 'fred' };
+ *
+ * var bound = _.bind(greet, object, 'hi');
+ * bound('!');
+ * // => 'hi fred!'
+ *
+ * // using placeholders
+ * var bound = _.bind(greet, object, _, '!');
+ * bound('hi');
+ * // => 'hi fred!'
+ */
+function bind(func, thisArg) {
+  var bitmask = BIND_FLAG;
+  if (arguments.length > 2) {
+    var partials = baseSlice(arguments, 2),
+        holders = replaceHolders(partials, bind.placeholder);
+
+    bitmask |= PARTIAL_FLAG;
+  }
+  return createWrapper(func, bitmask, thisArg, partials, holders);
+}
+
+// Assign default placeholders.
+bind.placeholder = {};
+
+export default bind;

function/bindAll.js

@@ -0,0 +1,39 @@
+import baseBindAll from '../internal/baseBindAll';
+import baseFlatten from '../internal/baseFlatten';
+import functions from '../object/functions';
+
+/**
+ * Binds methods of an object to the object itself, overwriting the existing
+ * method. Method names may be specified as individual arguments or as arrays
+ * of method names. If no method names are provided all enumerable function
+ * properties, own and inherited, of `object` are bound.
+ *
+ * **Note:** This method does not set the `length` property of bound functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Object} object The object to bind and assign the bound methods to.
+ * @param {...(string|string[])} [methodNames] The object method names to bind,
+ *  specified as individual method names or arrays of method names.
+ * @returns {Object} Returns `object`.
+ * @example
+ *
+ * var view = {
+ *   'label': 'docs',
+ *   'onClick': function() { console.log('clicked ' + this.label); }
+ * };
+ *
+ * _.bindAll(view);
+ * jQuery('#docs').on('click', view.onClick);
+ * // => logs 'clicked docs' when the element is clicked
+ */
+function bindAll(object) {
+  return baseBindAll(object,
+    arguments.length > 1
+      ? baseFlatten(arguments, false, false, 1)
+      : functions(object)
+  );
+}
+
+export default bindAll;

function/bindKey.js

@@ -0,0 +1,68 @@
+import baseSlice from '../internal/baseSlice';
+import createWrapper from '../internal/createWrapper';
+import replaceHolders from '../internal/replaceHolders';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var BIND_FLAG = 1,
+    BIND_KEY_FLAG = 2,
+    PARTIAL_FLAG = 32;
+
+/**
+ * Creates a function that invokes the method at `object[key]` and prepends
+ * any additional `_.bindKey` arguments to those provided to the bound function.
+ *
+ * This method differs from `_.bind` by allowing bound functions to reference
+ * methods that may be redefined or don't yet exist.
+ * See [Peter Michaux's article](http://michaux.ca/articles/lazy-function-definition-pattern)
+ * for more details.
+ *
+ * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic
+ * builds, may be used as a placeholder for partially applied arguments.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Object} object The object the method belongs to.
+ * @param {string} key The key of the method.
+ * @param {...*} [args] The arguments to be partially applied.
+ * @returns {Function} Returns the new bound function.
+ * @example
+ *
+ * var object = {
+ *   'user': 'fred',
+ *   'greet': function(greeting, punctuation) {
+ *     return greeting + ' ' + this.user + punctuation;
+ *   }
+ * };
+ *
+ * var bound = _.bindKey(object, 'greet', 'hi');
+ * bound('!');
+ * // => 'hi fred!'
+ *
+ * object.greet = function(greeting, punctuation) {
+ *   return greeting + 'ya ' + this.user + punctuation;
+ * };
+ *
+ * bound('!');
+ * // => 'hiya fred!'
+ *
+ * // using placeholders
+ * var bound = _.bindKey(object, 'greet', _, '!');
+ * bound('hi');
+ * // => 'hiya fred!'
+ */
+function bindKey(object, key) {
+  var bitmask = BIND_FLAG | BIND_KEY_FLAG;
+  if (arguments.length > 2) {
+    var partials = baseSlice(arguments, 2),
+        holders = replaceHolders(partials, bindKey.placeholder);
+
+    bitmask |= PARTIAL_FLAG;
+  }
+  return createWrapper(key, bitmask, object, partials, holders);
+}
+
+// Assign default placeholders.
+bindKey.placeholder = {};
+
+export default bindKey;

function/compose.js

@@ -0,0 +1,2 @@
+import flowRight from './flowRight'
+export default flowRight;

function/curry.js

@@ -0,0 +1,59 @@
+import createWrapper from '../internal/createWrapper';
+import isIterateeCall from '../internal/isIterateeCall';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var CURRY_FLAG = 8;
+
+/**
+ * Creates a function that accepts one or more arguments of `func` that when
+ * called either invokes `func` returning its result, if all `func` arguments
+ * have been provided, or returns a function that accepts one or more of the
+ * remaining `func` arguments, and so on. The arity of `func` may be specified
+ * if `func.length` is not sufficient.
+ *
+ * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
+ * may be used as a placeholder for provided arguments.
+ *
+ * **Note:** This method does not set the `length` property of curried functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to curry.
+ * @param {number} [arity=func.length] The arity of `func`.
+ * @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
+ * @returns {Function} Returns the new curried function.
+ * @example
+ *
+ * var abc = function(a, b, c) {
+ *   return [a, b, c];
+ * };
+ *
+ * var curried = _.curry(abc);
+ *
+ * curried(1)(2)(3);
+ * // => [1, 2, 3]
+ *
+ * curried(1, 2)(3);
+ * // => [1, 2, 3]
+ *
+ * curried(1, 2, 3);
+ * // => [1, 2, 3]
+ *
+ * // using placeholders
+ * curried(1)(_, 3)(2);
+ * // => [1, 2, 3]
+ */
+function curry(func, arity, guard) {
+  if (guard && isIterateeCall(func, arity, guard)) {
+    arity = null;
+  }
+  var result = createWrapper(func, CURRY_FLAG, null, null, null, null, null, arity);
+  result.placeholder = curry.placeholder;
+  return result;
+}
+
+// Assign default placeholders.
+curry.placeholder = {};
+
+export default curry;

function/curryRight.js

@@ -0,0 +1,56 @@
+import createWrapper from '../internal/createWrapper';
+import isIterateeCall from '../internal/isIterateeCall';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var CURRY_RIGHT_FLAG = 16;
+
+/**
+ * This method is like `_.curry` except that arguments are applied to `func`
+ * in the manner of `_.partialRight` instead of `_.partial`.
+ *
+ * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic
+ * builds, may be used as a placeholder for provided arguments.
+ *
+ * **Note:** This method does not set the `length` property of curried functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to curry.
+ * @param {number} [arity=func.length] The arity of `func`.
+ * @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
+ * @returns {Function} Returns the new curried function.
+ * @example
+ *
+ * var abc = function(a, b, c) {
+ *   return [a, b, c];
+ * };
+ *
+ * var curried = _.curryRight(abc);
+ *
+ * curried(3)(2)(1);
+ * // => [1, 2, 3]
+ *
+ * curried(2, 3)(1);
+ * // => [1, 2, 3]
+ *
+ * curried(1, 2, 3);
+ * // => [1, 2, 3]
+ *
+ * // using placeholders
+ * curried(3)(1, _)(2);
+ * // => [1, 2, 3]
+ */
+function curryRight(func, arity, guard) {
+  if (guard && isIterateeCall(func, arity, guard)) {
+    arity = null;
+  }
+  var result = createWrapper(func, CURRY_RIGHT_FLAG, null, null, null, null, null, arity);
+  result.placeholder = curryRight.placeholder;
+  return result;
+}
+
+// Assign default placeholders.
+curryRight.placeholder = {};
+
+export default curryRight;

function/debounce.js

@@ -0,0 +1,187 @@
+import isFunction from '../lang/isFunction';
+import isObject from '../lang/isObject';
+import now from '../date/now';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/* Native method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
+
+/**
+ * Creates a function that delays invoking `func` until after `wait` milliseconds
+ * have elapsed since the last time it was invoked. The created function comes
+ * with a `cancel` method to cancel delayed invocations. Provide an options
+ * object to indicate that `func` should be invoked on the leading and/or
+ * trailing edge of the `wait` timeout. Subsequent calls to the debounced
+ * function return the result of the last `func` invocation.
+ *
+ * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
+ * on the trailing edge of the timeout only if the the debounced function is
+ * invoked more than once during the `wait` timeout.
+ *
+ * See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
+ * for details over the differences between `_.debounce` and `_.throttle`.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to debounce.
+ * @param {number} wait The number of milliseconds to delay.
+ * @param {Object} [options] The options object.
+ * @param {boolean} [options.leading=false] Specify invoking on the leading
+ *  edge of the timeout.
+ * @param {number} [options.maxWait] The maximum time `func` is allowed to be
+ *  delayed before it is invoked.
+ * @param {boolean} [options.trailing=true] Specify invoking on the trailing
+ *  edge of the timeout.
+ * @returns {Function} Returns the new debounced function.
+ * @example
+ *
+ * // avoid costly calculations while the window size is in flux
+ * jQuery(window).on('resize', _.debounce(calculateLayout, 150));
+ *
+ * // invoke `sendMail` when the click event is fired, debouncing subsequent calls
+ * jQuery('#postbox').on('click', _.debounce(sendMail, 300, {
+ *   'leading': true,
+ *   'trailing': false
+ * }));
+ *
+ * // ensure `batchLog` is invoked once after 1 second of debounced calls
+ * var source = new EventSource('/stream');
+ * jQuery(source).on('message', _.debounce(batchLog, 250, {
+ *   'maxWait': 1000
+ * }));
+ *
+ * // cancel a debounced call
+ * var todoChanges = _.debounce(batchLog, 1000);
+ * Object.observe(models.todo, todoChanges);
+ *
+ * Object.observe(models, function(changes) {
+ *   if (_.find(changes, { 'user': 'todo', 'type': 'delete'})) {
+ *     todoChanges.cancel();
+ *   }
+ * }, ['delete']);
+ *
+ * // ...at some point `models.todo` is changed
+ * models.todo.completed = true;
+ *
+ * // ...before 1 second has passed `models.todo` is deleted
+ * // which cancels the debounced `todoChanges` call
+ * delete models.todo;
+ */
+function debounce(func, wait, options) {
+  var args,
+      maxTimeoutId,
+      result,
+      stamp,
+      thisArg,
+      timeoutId,
+      trailingCall,
+      lastCalled = 0,
+      maxWait = false,
+      trailing = true;
+
+  if (!isFunction(func)) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  wait = wait < 0 ? 0 : wait;
+  if (options === true) {
+    var leading = true;
+    trailing = false;
+  } else if (isObject(options)) {
+    leading = options.leading;
+    maxWait = 'maxWait' in options && nativeMax(+options.maxWait || 0, wait);
+    trailing = 'trailing' in options ? options.trailing : trailing;
+  }
+
+  function cancel() {
+    if (timeoutId) {
+      clearTimeout(timeoutId);
+    }
+    if (maxTimeoutId) {
+      clearTimeout(maxTimeoutId);
+    }
+    maxTimeoutId = timeoutId = trailingCall = undefined;
+  }
+
+  function delayed() {
+    var remaining = wait - (now() - stamp);
+    if (remaining <= 0 || remaining > wait) {
+      if (maxTimeoutId) {
+        clearTimeout(maxTimeoutId);
+      }
+      var isCalled = trailingCall;
+      maxTimeoutId = timeoutId = trailingCall = undefined;
+      if (isCalled) {
+        lastCalled = now();
+        result = func.apply(thisArg, args);
+        if (!timeoutId && !maxTimeoutId) {
+          args = thisArg = null;
+        }
+      }
+    } else {
+      timeoutId = setTimeout(delayed, remaining);
+    }
+  }
+
+  function maxDelayed() {
+    if (timeoutId) {
+      clearTimeout(timeoutId);
+    }
+    maxTimeoutId = timeoutId = trailingCall = undefined;
+    if (trailing || (maxWait !== wait)) {
+      lastCalled = now();
+      result = func.apply(thisArg, args);
+      if (!timeoutId && !maxTimeoutId) {
+        args = thisArg = null;
+      }
+    }
+  }
+
+  function debounced() {
+    args = arguments;
+    stamp = now();
+    thisArg = this;
+    trailingCall = trailing && (timeoutId || !leading);
+
+    if (maxWait === false) {
+      var leadingCall = leading && !timeoutId;
+    } else {
+      if (!maxTimeoutId && !leading) {
+        lastCalled = stamp;
+      }
+      var remaining = maxWait - (stamp - lastCalled),
+          isCalled = remaining <= 0 || remaining > maxWait;
+
+      if (isCalled) {
+        if (maxTimeoutId) {
+          maxTimeoutId = clearTimeout(maxTimeoutId);
+        }
+        lastCalled = stamp;
+        result = func.apply(thisArg, args);
+      }
+      else if (!maxTimeoutId) {
+        maxTimeoutId = setTimeout(maxDelayed, remaining);
+      }
+    }
+    if (isCalled && timeoutId) {
+      timeoutId = clearTimeout(timeoutId);
+    }
+    else if (!timeoutId && wait !== maxWait) {
+      timeoutId = setTimeout(delayed, wait);
+    }
+    if (leadingCall) {
+      isCalled = true;
+      result = func.apply(thisArg, args);
+    }
+    if (isCalled && !timeoutId && !maxTimeoutId) {
+      args = thisArg = null;
+    }
+    return result;
+  }
+  debounced.cancel = cancel;
+  return debounced;
+}
+
+export default debounce;

function/defer.js

@@ -0,0 +1,22 @@
+import baseDelay from '../internal/baseDelay';
+
+/**
+ * Defers invoking the `func` until the current call stack has cleared. Any
+ * additional arguments are provided to `func` when it is invoked.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to defer.
+ * @param {...*} [args] The arguments to invoke the function with.
+ * @returns {number} Returns the timer id.
+ * @example
+ *
+ * _.defer(function(text) { console.log(text); }, 'deferred');
+ * // logs 'deferred' after one or more milliseconds
+ */
+function defer(func) {
+  return baseDelay(func, 1, arguments, 1);
+}
+
+export default defer;

function/delay.js

@@ -0,0 +1,23 @@
+import baseDelay from '../internal/baseDelay';
+
+/**
+ * Invokes `func` after `wait` milliseconds. Any additional arguments are
+ * provided to `func` when it is invoked.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to delay.
+ * @param {number} wait The number of milliseconds to delay invocation.
+ * @param {...*} [args] The arguments to invoke the function with.
+ * @returns {number} Returns the timer id.
+ * @example
+ *
+ * _.delay(function(text) { console.log(text); }, 1000, 'later');
+ * // => logs 'later' after one second
+ */
+function delay(func, wait) {
+  return baseDelay(func, wait, arguments, 2);
+}
+
+export default delay;

function/flow.js

@@ -0,0 +1,52 @@
+import arrayEvery from '../internal/arrayEvery';
+import isFunction from '../lang/isFunction';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/**
+ * Creates a function that returns the result of invoking the provided
+ * functions with the `this` binding of the created function, where each
+ * successive invocation is supplied the return value of the previous.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {...Function} [funcs] Functions to invoke.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * function add(x, y) {
+ *   return x + y;
+ * }
+ *
+ * function square(n) {
+ *   return n * n;
+ * }
+ *
+ * var addSquare = _.flow(add, square);
+ * addSquare(1, 2);
+ * // => 9
+ */
+function flow() {
+  var funcs = arguments,
+      length = funcs.length;
+
+  if (!length) {
+    return function() {};
+  }
+  if (!arrayEvery(funcs, isFunction)) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  return function() {
+    var index = 0,
+        result = funcs[index].apply(this, arguments);
+
+    while (++index < length) {
+      result = funcs[index].call(this, result);
+    }
+    return result;
+  };
+}
+
+export default flow;

function/flowRight.js

@@ -0,0 +1,52 @@
+import arrayEvery from '../internal/arrayEvery';
+import isFunction from '../lang/isFunction';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/**
+ * This method is like `_.flow` except that it creates a function that
+ * invokes the provided functions from right to left.
+ *
+ * @static
+ * @memberOf _
+ * @alias backflow, compose
+ * @category Function
+ * @param {...Function} [funcs] Functions to invoke.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * function add(x, y) {
+ *   return x + y;
+ * }
+ *
+ * function square(n) {
+ *   return n * n;
+ * }
+ *
+ * var addSquare = _.flowRight(square, add);
+ * addSquare(1, 2);
+ * // => 9
+ */
+function flowRight() {
+  var funcs = arguments,
+      fromIndex = funcs.length - 1;
+
+  if (fromIndex < 0) {
+    return function() {};
+  }
+  if (!arrayEvery(funcs, isFunction)) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  return function() {
+    var index = fromIndex,
+        result = funcs[index].apply(this, arguments);
+
+    while (index--) {
+      result = funcs[index].call(this, result);
+    }
+    return result;
+  };
+}
+
+export default flowRight;

function/memoize.js

@@ -0,0 +1,82 @@
+import MapCache from '../internal/MapCache';
+import isFunction from '../lang/isFunction';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/**
+ * Creates a function that memoizes the result of `func`. If `resolver` is
+ * provided it determines the cache key for storing the result based on the
+ * arguments provided to the memoized function. By default, the first argument
+ * provided to the memoized function is coerced to a string and used as the
+ * cache key. The `func` is invoked with the `this` binding of the memoized
+ * function.
+ *
+ * **Note:** The cache is exposed as the `cache` property on the memoized
+ * function. Its creation may be customized by replacing the `_.memoize.Cache`
+ * constructor with one whose instances implement the ES `Map` method interface
+ * of `get`, `has`, and `set`. See the
+ * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-properties-of-the-map-prototype-object)
+ * for more details.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to have its output memoized.
+ * @param {Function} [resolver] The function to resolve the cache key.
+ * @returns {Function} Returns the new memoizing function.
+ * @example
+ *
+ * var upperCase = _.memoize(function(string) {
+ *   return string.toUpperCase();
+ * });
+ *
+ * upperCase('fred');
+ * // => 'FRED'
+ *
+ * // modifying the result cache
+ * upperCase.cache.set('fred, 'BARNEY');
+ * upperCase('fred');
+ * // => 'BARNEY'
+ *
+ * // replacing `_.memoize.Cache`
+ * var object = { 'user': 'fred' };
+ * var other = { 'user': 'barney' };
+ * var identity = _.memoize(_.identity);
+ *
+ * identity(object);
+ * // => { 'user': 'fred' }
+ * identity(other);
+ * // => { 'user': 'fred' }
+ *
+ * _.memoize.Cache = WeakMap;
+ * var identity = _.memoize(_.identity);
+ *
+ * identity(object);
+ * // => { 'user': 'fred' }
+ * identity(other);
+ * // => { 'user': 'barney' }
+ */
+function memoize(func, resolver) {
+  if (!isFunction(func) || (resolver && !isFunction(resolver))) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  var memoized = function() {
+    var cache = memoized.cache,
+        key = resolver ? resolver.apply(this, arguments) : arguments[0];
+
+    if (cache.has(key)) {
+      return cache.get(key);
+    }
+    var result = func.apply(this, arguments);
+    cache.set(key, result);
+    return result;
+  };
+  memoized.cache = new memoize.Cache;
+  return memoized;
+}
+
+// Assign cache to `_.memoize`.
+memoize.Cache = MapCache;
+
+export default memoize;

function/negate.js

@@ -0,0 +1,34 @@
+import isFunction from '../lang/isFunction';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/**
+ * Creates a function that negates the result of the predicate `func`. The
+ * `func` predicate is invoked with the `this` binding and arguments of the
+ * created function.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} predicate The predicate to negate.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * function isEven(n) {
+ *   return n % 2 == 0;
+ * }
+ *
+ * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
+ * // => [1, 3, 5]
+ */
+function negate(predicate) {
+  if (!isFunction(predicate)) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  return function() {
+    return !predicate.apply(this, arguments);
+  };
+}
+
+export default negate;

function/once.js

@@ -0,0 +1,25 @@
+import before from './before';
+
+/**
+ * Creates a function that is restricted to invoking `func` once. Repeat calls
+ * to the function return the value of the first call. The `func` is invoked
+ * with the `this` binding of the created function.
+ *
+ * @static
+ * @memberOf _
+ * @type Function
+ * @category Function
+ * @param {Function} func The function to restrict.
+ * @returns {Function} Returns the new restricted function.
+ * @example
+ *
+ * var initialize = _.once(createApplication);
+ * initialize();
+ * initialize();
+ * // `initialize` invokes `createApplication` once
+ */
+function once(func) {
+  return before(func, 2);
+}
+
+export default once;

function/partial.js

@@ -0,0 +1,50 @@
+import baseSlice from '../internal/baseSlice';
+import createWrapper from '../internal/createWrapper';
+import replaceHolders from '../internal/replaceHolders';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var PARTIAL_FLAG = 32;
+
+/**
+ * Creates a function that invokes `func` with `partial` arguments prepended
+ * to those provided to the new function. This method is like `_.bind` except
+ * it does **not** alter the `this` binding.
+ *
+ * The `_.partial.placeholder` value, which defaults to `_` in monolithic
+ * builds, may be used as a placeholder for partially applied arguments.
+ *
+ * **Note:** This method does not set the `length` property of partially
+ * applied functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to partially apply arguments to.
+ * @param {...*} [args] The arguments to be partially applied.
+ * @returns {Function} Returns the new partially applied function.
+ * @example
+ *
+ * var greet = function(greeting, name) {
+ *   return greeting + ' ' + name;
+ * };
+ *
+ * var sayHelloTo = _.partial(greet, 'hello');
+ * sayHelloTo('fred');
+ * // => 'hello fred'
+ *
+ * // using placeholders
+ * var greetFred = _.partial(greet, _, 'fred');
+ * greetFred('hi');
+ * // => 'hi fred'
+ */
+function partial(func) {
+  var partials = baseSlice(arguments, 1),
+      holders = replaceHolders(partials, partial.placeholder);
+
+  return createWrapper(func, PARTIAL_FLAG, null, partials, holders);
+}
+
+// Assign default placeholders.
+partial.placeholder = {};
+
+export default partial;

function/partialRight.js

@@ -0,0 +1,49 @@
+import baseSlice from '../internal/baseSlice';
+import createWrapper from '../internal/createWrapper';
+import replaceHolders from '../internal/replaceHolders';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var PARTIAL_RIGHT_FLAG = 64;
+
+/**
+ * This method is like `_.partial` except that partially applied arguments
+ * are appended to those provided to the new function.
+ *
+ * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic
+ * builds, may be used as a placeholder for partially applied arguments.
+ *
+ * **Note:** This method does not set the `length` property of partially
+ * applied functions.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to partially apply arguments to.
+ * @param {...*} [args] The arguments to be partially applied.
+ * @returns {Function} Returns the new partially applied function.
+ * @example
+ *
+ * var greet = function(greeting, name) {
+ *   return greeting + ' ' + name;
+ * };
+ *
+ * var greetFred = _.partialRight(greet, 'fred');
+ * greetFred('hi');
+ * // => 'hi fred'
+ *
+ * // using placeholders
+ * var sayHelloTo = _.partialRight(greet, 'hello', _);
+ * sayHelloTo('fred');
+ * // => 'hello fred'
+ */
+function partialRight(func) {
+  var partials = baseSlice(arguments, 1),
+      holders = replaceHolders(partials, partialRight.placeholder);
+
+  return createWrapper(func, PARTIAL_RIGHT_FLAG, null, partials, holders);
+}
+
+// Assign default placeholders.
+partialRight.placeholder = {};
+
+export default partialRight;

function/rearg.js

@@ -0,0 +1,38 @@
+import baseFlatten from '../internal/baseFlatten';
+import createWrapper from '../internal/createWrapper';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var REARG_FLAG = 128;
+
+/**
+ * Creates a function that invokes `func` with arguments arranged according
+ * to the specified indexes where the argument value at the first index is
+ * provided as the first argument, the argument value at the second index is
+ * provided as the second argument, and so on.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to rearrange arguments for.
+ * @param {...(number|number[])} indexes The arranged argument indexes,
+ *  specified as individual indexes or arrays of indexes.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * var rearged = _.rearg(function(a, b, c) {
+ *   return [a, b, c];
+ * }, 2, 0, 1);
+ *
+ * rearged('b', 'c', 'a')
+ * // => ['a', 'b', 'c']
+ *
+ * var map = _.rearg(_.map, [1, 0]);
+ * map(function(n) { return n * 3; }, [1, 2, 3]);
+ * // => [3, 6, 9]
+ */
+function rearg(func) {
+  var indexes = baseFlatten(arguments, false, false, 1);
+  return createWrapper(func, REARG_FLAG, null, null, null, indexes);
+}
+
+export default rearg;

function/throttle.js

@@ -0,0 +1,72 @@
+import debounce from './debounce';
+import isFunction from '../lang/isFunction';
+import isObject from '../lang/isObject';
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/** Used as an internal `_.debounce` options object by `_.throttle`. */
+var debounceOptions = {
+  'leading': false,
+  'maxWait': 0,
+  'trailing': false
+};
+
+/**
+ * Creates a function that only invokes `func` at most once per every `wait`
+ * milliseconds. The created function comes with a `cancel` method to cancel
+ * delayed invocations. Provide an options object to indicate that `func`
+ * should be invoked on the leading and/or trailing edge of the `wait` timeout.
+ * Subsequent calls to the throttled function return the result of the last
+ * `func` call.
+ *
+ * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
+ * on the trailing edge of the timeout only if the the throttled function is
+ * invoked more than once during the `wait` timeout.
+ *
+ * See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
+ * for details over the differences between `_.throttle` and `_.debounce`.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to throttle.
+ * @param {number} wait The number of milliseconds to throttle invocations to.
+ * @param {Object} [options] The options object.
+ * @param {boolean} [options.leading=true] Specify invoking on the leading
+ *  edge of the timeout.
+ * @param {boolean} [options.trailing=true] Specify invoking on the trailing
+ *  edge of the timeout.
+ * @returns {Function} Returns the new throttled function.
+ * @example
+ *
+ * // avoid excessively updating the position while scrolling
+ * jQuery(window).on('scroll', _.throttle(updatePosition, 100));
+ *
+ * // invoke `renewToken` when the click event is fired, but not more than once every 5 minutes
+ * var throttled =  _.throttle(renewToken, 300000, { 'trailing': false })
+ * jQuery('.interactive').on('click', throttled);
+ *
+ * // cancel a trailing throttled call
+ * jQuery(window).on('popstate', throttled.cancel);
+ */
+function throttle(func, wait, options) {
+  var leading = true,
+      trailing = true;
+
+  if (!isFunction(func)) {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  if (options === false) {
+    leading = false;
+  } else if (isObject(options)) {
+    leading = 'leading' in options ? !!options.leading : leading;
+    trailing = 'trailing' in options ? !!options.trailing : trailing;
+  }
+  debounceOptions.leading = leading;
+  debounceOptions.maxWait = +wait;
+  debounceOptions.trailing = trailing;
+  return debounce(func, wait, debounceOptions);
+}
+
+export default throttle;

function/wrap.js

@@ -0,0 +1,33 @@
+import createWrapper from '../internal/createWrapper';
+import identity from '../utility/identity';
+
+/** Used to compose bitmasks for wrapper metadata. */
+var PARTIAL_FLAG = 32;
+
+/**
+ * Creates a function that provides `value` to the wrapper function as its
+ * first argument. Any additional arguments provided to the function are
+ * appended to those provided to the wrapper function. The wrapper is invoked
+ * with the `this` binding of the created function.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {*} value The value to wrap.
+ * @param {Function} wrapper The wrapper function.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * var p = _.wrap(_.escape, function(func, text) {
+ *   return '<p>' + func(text) + '</p>';
+ * });
+ *
+ * p('fred, barney, & pebbles');
+ * // => '<p>fred, barney, &amp; pebbles</p>'
+ */
+function wrap(value, wrapper) {
+  wrapper = wrapper == null ? identity : wrapper;
+  return createWrapper(wrapper, PARTIAL_FLAG, null, [value], []);
+}
+
+export default wrap;