stalker-pattern

Stalker-pattern is a Javascript pattern with a promise-like syntax streaming but in which the whole stream is re-triggerable like an event. Additionally it also supports synchronous triggering.

##API A basic notion of Promises will help you easily understand this pattern.

Basics

var Stalker = require('stalker-pattern');

var myStalker = new Stalker(function(trigger){
  trigger("hi!");
});

myStalker.follow(function(result){
  console.log(result); //prints "hi!"
});

Chaining stalkers

var myStalker = new Stalker(function(trigger){

  trigger(new Stalker(function(t){
    t("More complex");

    setTimeout(function(){
      t("Async");
    })
  }));

}).follow(function(result){

  return new Stalker(function(t2){
    t2(result+" hi!");
  });

}).follow(function(result){

  // prints "More complex hi!",
  // and then on next tick prints "Async hi!"
  console.log(result);

});

Piping only a few occurrences

new Stalker(function(trigger){

  trigger(1);
  trigger(2);
  trigger(3);
  trigger(4);

}).from(1).to(3).follow(function(number){

  console.log(number); //prints 1,2,3
  return number;

}).the(2).follow(function(number){

  console.log(number); //prints 2
  return number;

}).first().follow(function(number){

  console.log(number); //prints 2

});

//stack prints:
//1, 2, 3, 2, 2

Note: In the case above "1","2","3" all fire in the first follow() before "2" is propagated down to the 2nd follow(). This is the default behaviour of Stalker for syncrounous triggering