add hw2

node_modules/lodash/bind.js

@@ -0,0 +1,57 @@
+var baseRest = require('./_baseRest'),
+    createWrap = require('./_createWrap'),
+    getHolder = require('./_getHolder'),
+    replaceHolders = require('./_replaceHolders');
+
+/** Used to compose bitmasks for function metadata. */
+var WRAP_BIND_FLAG = 1,
+    WRAP_PARTIAL_FLAG = 32;
+
+/**
+ * Creates a function that invokes `func` with the `this` binding of `thisArg`
+ * and `partials` prepended to the arguments it receives.
+ *
+ * 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 doesn't set the "length"
+ * property of bound functions.
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Function
+ * @param {Function} func The function to bind.
+ * @param {*} thisArg The `this` binding of `func`.
+ * @param {...*} [partials] The arguments to be partially applied.
+ * @returns {Function} Returns the new bound function.
+ * @example
+ *
+ * function greet(greeting, punctuation) {
+ *   return greeting + ' ' + this.user + punctuation;
+ * }
+ *
+ * var object = { 'user': 'fred' };
+ *
+ * var bound = _.bind(greet, object, 'hi');
+ * bound('!');
+ * // => 'hi fred!'
+ *
+ * // Bound with placeholders.
+ * var bound = _.bind(greet, object, _, '!');
+ * bound('hi');
+ * // => 'hi fred!'
+ */
+var bind = baseRest(function(func, thisArg, partials) {
+  var bitmask = WRAP_BIND_FLAG;
+  if (partials.length) {
+    var holders = replaceHolders(partials, getHolder(bind));
+    bitmask |= WRAP_PARTIAL_FLAG;
+  }
+  return createWrap(func, bitmask, thisArg, partials, holders);
+});
+
+// Assign default placeholders.
+bind.placeholder = {};
+
+module.exports = bind;