document event emitter cache

README.md

@@ -1,7 +1,7 @@
 flexcache
 =======
 
-Flexible cache for async function calls. It is designed for preventing dirty caches more then on speed.
+Flexible cache for async function calls and event emitters. It is designed for preventing dirty caches more then on speed.
 Different Backends allows you to cover different usecases.
 
 
@@ -112,7 +112,15 @@ fc.clear_all()
 
 Whatever arguments are passed to cached, they are used to compute the subkey and should therefor never hit a wrong
 cache entry. 
-
+
+# EventEmitters
+
+The cache function can also generate EventEmitters. You need to specify emitter in which case you will get the eventemitter returned.
+If you specify a function all parameters are passed to it.
+It is important that the EventEmitter constructed in the emmiter function does no work at all.
+Events forwarded and reactet do are `data` and `end`.
+
+The cache is replayed the same way the data is generated by the original function, but every chunk is sent one tick after another.
 
 Advanced Usage
 --------------
@@ -132,6 +140,7 @@ fc = new Flexcache(backend, {
 rcached = fc.cache(slow, {
     group: function() { return self.somevalue },
     name: "somethinguniqe"
+    emitter: function() { return new MyEventemitter() },
     }); 
 
 
@@ -175,6 +184,7 @@ The returned function has special members which helps you to deal with cache con
   - `hash` same as hash. default: **one**
   - `name` identifier for hash
   - `multi` if set, don't complain about multiple caches sharing the same name
+  - `emitter` if set the function will return a event emitter and not run the callback. Can my true ( EventEmitter ) or a simple EventEmitter class.
 
 
 ## cache(...).clear\_group([args,...])