Core changes from #8

src/core.js

@@ -1,120 +1,129 @@
-function WildEmitter() {
-    this.isWildEmitter = true;
-    this.callbacks = {};
-}
-
-// Listen on the given `event` with `fn`. Store a group name if present.
-WildEmitter.prototype.on = function (event, groupName, fn) {
-    var hasGroup = (arguments.length === 3),
-        group = hasGroup ? arguments[1] : undefined,
-        func = hasGroup ? arguments[2] : arguments[1];
-    func._groupName = group;
-    (this.callbacks[event] = this.callbacks[event] || []).push(func);
-    return this;
-};
+function WildEmitter() { }
 
-// Adds an `event` listener that will be invoked a single
-// time then automatically removed.
-WildEmitter.prototype.once = function (event, groupName, fn) {
-    var self = this,
-        hasGroup = (arguments.length === 3),
-        group = hasGroup ? arguments[1] : undefined,
-        func = hasGroup ? arguments[2] : arguments[1];
-    function on() {
-        self.off(event, on);
-        func.apply(this, arguments);
-    }
-    this.on(event, group, on);
-    return this;
-};
+WildEmitter.mixin = function (constructor) {
+    var prototype = constructor.prototype || constructor;
+
+    // Listen on the given `event` with `fn`. Store a group name if present.
+    prototype.on = function (event, groupName, fn) {
+        this.callbacks = this.callbacks || {};
+        var hasGroup = (arguments.length === 3),
+            group = hasGroup ? arguments[1] : undefined,
+            func = hasGroup ? arguments[2] : arguments[1];
+        func._groupName = group;
+        (this.callbacks[event] = this.callbacks[event] || []).push(func);
+        return this;
+    };
+
+    // Adds an `event` listener that will be invoked a single
+    // time then automatically removed.
+    prototype.once = function (event, groupName, fn) {
+        var self = this,
+            hasGroup = (arguments.length === 3),
+            group = hasGroup ? arguments[1] : undefined,
+            func = hasGroup ? arguments[2] : arguments[1];
+        function on() {
+            self.off(event, on);
+            func.apply(this, arguments);
+        }
+        this.on(event, group, on);
+        return this;
+    };
 
-// Unbinds an entire group
-WildEmitter.prototype.releaseGroup = function (groupName) {
-    var item, i, len, handlers;
-    for (item in this.callbacks) {
-        handlers = this.callbacks[item];
-        for (i = 0, len = handlers.length; i < len; i++) {
-            if (handlers[i]._groupName === groupName) {
-                //console.log('removing');
-                // remove it and shorten the array we're looping through
-                handlers.splice(i, 1);
-                i--;
-                len--;
+    // Unbinds an entire group
+    prototype.releaseGroup = function (groupName) {
+        this.callbacks = this.callbacks || {};
+        var item, i, len, handlers;
+        for (item in this.callbacks) {
+            handlers = this.callbacks[item];
+            for (i = 0, len = handlers.length; i < len; i++) {
+                if (handlers[i]._groupName === groupName) {
+                    //console.log('removing');
+                    // remove it and shorten the array we're looping through
+                    handlers.splice(i, 1);
+                    i--;
+                    len--;
+                }
             }
         }
-    }
-    return this;
-};
+        return this;
+    };
+
+    // Remove the given callback for `event` or all
+    // registered callbacks.
+    prototype.off = function (event, fn) {
+        this.callbacks = this.callbacks || {};
+        var callbacks = this.callbacks[event],
+            i;
 
-// Remove the given callback for `event` or all
-// registered callbacks.
-WildEmitter.prototype.off = function (event, fn) {
-    var callbacks = this.callbacks[event],
-        i;
+        if (!callbacks) return this;
 
-    if (!callbacks) return this;
+        // remove all handlers
+        if (arguments.length === 1) {
+            delete this.callbacks[event];
+            return this;
+        }
 
-    // remove all handlers
-    if (arguments.length === 1) {
-        delete this.callbacks[event];
+        // remove specific handler
+        i = callbacks.indexOf(fn);
+        callbacks.splice(i, 1);
+        if (callbacks.length === 0) {
+            delete this.callbacks[event];
+        }
         return this;
-    }
-
-    // remove specific handler
-    i = callbacks.indexOf(fn);
-    callbacks.splice(i, 1);
-    if (callbacks.length === 0) {
-        delete this.callbacks[event];
-    }
-    return this;
-};
+    };
 
-/// Emit `event` with the given args.
-// also calls any `*` handlers
-WildEmitter.prototype.emit = function (event) {
-    var args = [].slice.call(arguments, 1),
-        callbacks = this.callbacks[event],
-        specialCallbacks = this.getWildcardCallbacks(event),
-        i,
-        len,
-        item,
-        listeners;
-
-    if (callbacks) {
-        listeners = callbacks.slice();
-        for (i = 0, len = listeners.length; i < len; ++i) {
-            if (!listeners[i]) {
-                break;
+    /// Emit `event` with the given args.
+    // also calls any `*` handlers
+    prototype.emit = function (event) {
+        this.callbacks = this.callbacks || {};
+        var args = [].slice.call(arguments, 1),
+            callbacks = this.callbacks[event],
+            specialCallbacks = this.getWildcardCallbacks(event),
+            i,
+            len,
+            item,
+            listeners;
+
+        if (callbacks) {
+            listeners = callbacks.slice();
+            for (i = 0, len = listeners.length; i < len; ++i) {
+                if (!listeners[i]) {
+                    break;
+                }
+                listeners[i].apply(this, args);
             }
-            listeners[i].apply(this, args);
         }
-    }
-
-    if (specialCallbacks) {
-        len = specialCallbacks.length;
-        listeners = specialCallbacks.slice();
-        for (i = 0, len = listeners.length; i < len; ++i) {
-            if (!listeners[i]) {
-                break;
+
+        if (specialCallbacks) {
+            len = specialCallbacks.length;
+            listeners = specialCallbacks.slice();
+            for (i = 0, len = listeners.length; i < len; ++i) {
+                if (!listeners[i]) {
+                    break;
+                }
+                listeners[i].apply(this, [event].concat(args));
             }
-            listeners[i].apply(this, [event].concat(args));
         }
-    }
 
-    return this;
-};
+        return this;
+    };
 
-// Helper for for finding special wildcard event handlers that match the event
-WildEmitter.prototype.getWildcardCallbacks = function (eventName) {
-    var item,
-        split,
-        result = [];
+    // Helper for for finding special wildcard event handlers that match the event
+    prototype.getWildcardCallbacks = function (eventName) {
+        this.callbacks = this.callbacks || {};
+        var item,
+            split,
+            result = [];
 
-    for (item in this.callbacks) {
-        split = item.split('*');
-        if (item === '*' || (split.length === 2 && eventName.slice(0, split[0].length) === split[0])) {
-            result = result.concat(this.callbacks[item]);
+        for (item in this.callbacks) {
+            split = item.split('*');
+            if (item === '*' || (split.length === 2 && eventName.slice(0, split[0].length) === split[0])) {
+                result = result.concat(this.callbacks[item]);
+            }
         }
-    }
-    return result;
+        return result;
+    };
+
 };
+
+WildEmitter.mixin(WildEmitter);