source: Dev/trunk/src/client/dojox/lang/aspect/memoizer.js

dojo.provide("dojox.lang.aspect.memoizer");

(function(){
        var aop = dojox.lang.aspect;

        var memoize1 = {
                around: function(key){
                        var ctx = aop.getContext(), self = ctx.joinPoint, that = ctx.instance, t, u, ret;
                        if((t = that.__memoizerCache) && (t = t[self.targetName]) && (key in t)){
                                return t[key];
                        }
                        var ret = aop.proceed.apply(null, arguments);
                        if(!(t = that.__memoizerCache)){ t = that.__memoizerCache = {}; }
                        if(!(u = t[self.targetName])){ u = t[self.targetName] = {}; }
                        return u[key] = ret;
                }
        };

        var memoizeN = function(/*Function*/keyMaker){
                return {
                        around: function(/*arguments*/){
                                var ctx = aop.getContext(), self = ctx.joinPoint, that = ctx.instance, t, u, ret,
                                        key  = keyMaker.apply(that, arguments);
                                if((t = that.__memoizerCache) && (t = t[self.targetName]) && (key in t)){
                                        return t[key];
                                }
                                var ret = aop.proceed.apply(null, arguments);
                                if(!(t = that.__memoizerCache)){ t = that.__memoizerCache = {}; }
                                if(!(u = t[self.targetName])){ u = t[self.targetName] = {}; }
                                return u[key] = ret;
                        }
                };
        };

        aop.memoizer = function(/*Function?*/ keyMaker){
                // summary:
                //              Returns an object, which can be used to count calls to methods.
                //
                // keyMaker:
                //              the function, which takes method's arguments and returns a key,
                //              which can be used to index the result.

                return arguments.length == 0 ? memoize1 : memoizeN(keyMaker);   // Object
        };
})();