source: Dev/trunk/src/client/dojox/lang/oo/aop.js @ 532

dojo.provide("dojox.lang.oo.aop");

dojo.require("dojox.lang.oo.Decorator");
dojo.require("dojox.lang.oo.general");

(function(){
        var oo = dojox.lang.oo, md = oo.makeDecorator, oog = oo.general, ooa = oo.aop,
                isF = dojo.isFunction;

        // five decorators implementing light-weight AOP weaving

        // reuse existing decorators
        ooa.before = oog.before;
        ooa.around = oog.wrap;

        /*=====
        ooa.before = md(function(name, newValue, oldValue){
                // summary:
                //              creates a "before" advise, by calling new function
                //              before the old one

                // dummy body
        });

        ooa.around = md(function(name, newValue, oldValue){
                // summary:
                //              creates an "around" advise,
                //              the previous value is passed as a first argument and can be null,
                //              arguments are passed as a second argument

                // dummy body
        });
        =====*/


        ooa.afterReturning = md(function(name, newValue, oldValue){
                // summary:
                //              creates an "afterReturning" advise,
                //              the returned value is passed as the only argument
                return isF(oldValue) ?
                        function(){
                                var ret = oldValue.apply(this, arguments);
                                newValue.call(this, ret);
                                return ret;
                        } : function(){ newValue.call(this); };
        });

        ooa.afterThrowing = md(function(name, newValue, oldValue){
                // summary:
                //              creates an "afterThrowing" advise,
                //              the exception is passed as the only argument
                return isF(oldValue) ?
                        function(){
                                var ret;
                                try{
                                        ret = oldValue.apply(this, arguments);
                                }catch(e){
                                        newValue.call(this, e);
                                        throw e;
                                }
                                return ret;
                        } : oldValue;
        });

        ooa.after = md(function(name, newValue, oldValue){
                // summary:
                //              creates an "after" advise,
                //              it takes no arguments
                return isF(oldValue) ?
                        function(){
                                var ret;
                                try{
                                        ret = oldValue.apply(this, arguments);
                                }finally{
                                        newValue.call(this);
                                }
                                return ret;
                        } : function(){ newValue.call(this); }
        });
})();