causeeffect

Created to simplify flow management when programming in asynchronous environments like nodejs.

CauseEffect extends EventEmitter and allows to set cause-effect scenarios.

It is simple yet effective.

CauseEffect allows you to:
* have an event fired when multiple parallel flows complete.
* easily unite multiple parallel flows initiated from the for loop.
* set up chains: completion of one rule may trigger another.
* set the rules dynamically or statically.
* have an event fired when any of the flows completes.

To run example:
	node examples/sample.js

Installation: npm install causeeffect

Usage: To setup a rule where an event will fire if all of the causes happen: ce.setEvents("myevent", ["cause1", "cause2", "cause3"]);

To setup a rule where an event will fire if some of the causes happen:
	ce.setEvents("myevent", ["cause1", "cause2", "cause3"], true);

To setup a rule where an event will fire if it happens X times:
	ce.setEvents("myevent", 10);

Listen to effect event as usual with EventEmitter API:
	ce.on("myevent", callback);

To let CauseEffect know that the cause has happened call:
	ce.setState("cause1");
or if you need a specific value use
	ce.setState("cause1", value);
This value can be then obtained from your event callback with:
	ce.getState("cause1")

To run example:
	node examples/sample.js

Sample:

1. Uniting multiple parallel flows initiated from the for loop: var ce = require('causeeffect'); ce = new ce.CauseEffect();

   // Set up ticker cause. Event "myticker" will fire if ce.setState("myticker") was invoked 4 times. // Handy for figuring out when all callbacks have been called initiated from the for loop. ce.setEvents("myticker", 4);

   function callback() { ce.setState("myticker"); }

   for(var i = 0; i< 4; i++) { setTimeout(callback, 100); }

   ce.on("myticker", function() { });

2. Uniting specific parallel flows // Set up AND cause effect. Event "alldone" will be fired if all of causes happen ce.setEvents("alldone", ["cause1", "cause2", "myticker"]);

   // Listen to event as usual with EventEmitter API ce.on("alldone", function() { });

   // To let CauseEffect know that the cause has happened ce.setState("cause1"); ce.setState("cause2");