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-rw-r--r--node_modules/component-emitter/index.js163
1 files changed, 163 insertions, 0 deletions
diff --git a/node_modules/component-emitter/index.js b/node_modules/component-emitter/index.js
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+
+/**
+ * Expose `Emitter`.
+ */
+
+if (typeof module !== 'undefined') {
+ module.exports = Emitter;
+}
+
+/**
+ * Initialize a new `Emitter`.
+ *
+ * @api public
+ */
+
+function Emitter(obj) {
+ if (obj) return mixin(obj);
+};
+
+/**
+ * Mixin the emitter properties.
+ *
+ * @param {Object} obj
+ * @return {Object}
+ * @api private
+ */
+
+function mixin(obj) {
+ for (var key in Emitter.prototype) {
+ obj[key] = Emitter.prototype[key];
+ }
+ return obj;
+}
+
+/**
+ * Listen on the given `event` with `fn`.
+ *
+ * @param {String} event
+ * @param {Function} fn
+ * @return {Emitter}
+ * @api public
+ */
+
+Emitter.prototype.on =
+Emitter.prototype.addEventListener = function(event, fn){
+ this._callbacks = this._callbacks || {};
+ (this._callbacks['$' + event] = this._callbacks['$' + event] || [])
+ .push(fn);
+ return this;
+};
+
+/**
+ * Adds an `event` listener that will be invoked a single
+ * time then automatically removed.
+ *
+ * @param {String} event
+ * @param {Function} fn
+ * @return {Emitter}
+ * @api public
+ */
+
+Emitter.prototype.once = function(event, fn){
+ function on() {
+ this.off(event, on);
+ fn.apply(this, arguments);
+ }
+
+ on.fn = fn;
+ this.on(event, on);
+ return this;
+};
+
+/**
+ * Remove the given callback for `event` or all
+ * registered callbacks.
+ *
+ * @param {String} event
+ * @param {Function} fn
+ * @return {Emitter}
+ * @api public
+ */
+
+Emitter.prototype.off =
+Emitter.prototype.removeListener =
+Emitter.prototype.removeAllListeners =
+Emitter.prototype.removeEventListener = function(event, fn){
+ this._callbacks = this._callbacks || {};
+
+ // all
+ if (0 == arguments.length) {
+ this._callbacks = {};
+ return this;
+ }
+
+ // specific event
+ var callbacks = this._callbacks['$' + event];
+ if (!callbacks) return this;
+
+ // remove all handlers
+ if (1 == arguments.length) {
+ delete this._callbacks['$' + event];
+ return this;
+ }
+
+ // remove specific handler
+ var cb;
+ for (var i = 0; i < callbacks.length; i++) {
+ cb = callbacks[i];
+ if (cb === fn || cb.fn === fn) {
+ callbacks.splice(i, 1);
+ break;
+ }
+ }
+ return this;
+};
+
+/**
+ * Emit `event` with the given args.
+ *
+ * @param {String} event
+ * @param {Mixed} ...
+ * @return {Emitter}
+ */
+
+Emitter.prototype.emit = function(event){
+ this._callbacks = this._callbacks || {};
+ var args = [].slice.call(arguments, 1)
+ , callbacks = this._callbacks['$' + event];
+
+ if (callbacks) {
+ callbacks = callbacks.slice(0);
+ for (var i = 0, len = callbacks.length; i < len; ++i) {
+ callbacks[i].apply(this, args);
+ }
+ }
+
+ return this;
+};
+
+/**
+ * Return array of callbacks for `event`.
+ *
+ * @param {String} event
+ * @return {Array}
+ * @api public
+ */
+
+Emitter.prototype.listeners = function(event){
+ this._callbacks = this._callbacks || {};
+ return this._callbacks['$' + event] || [];
+};
+
+/**
+ * Check if this emitter has `event` handlers.
+ *
+ * @param {String} event
+ * @return {Boolean}
+ * @api public
+ */
+
+Emitter.prototype.hasListeners = function(event){
+ return !! this.listeners(event).length;
+};