Sets out a pattern for chaining methods and implementing native promises alongside a polyfill for unsupported browsers.
| /* | |
| * referenced Jake Archibald's http://www.html5rocks.com/en/tutorials/es6/promises/ | |
| */ | |
| (function(window, undefined){ | |
| window.chainit = function() | |
| { | |
| function Initialize() | |
| { | |
| this.methodpromise = new Promise(DoStuff); //-- initialize | |
| this.error = false; | |
| }; | |
| function DoStuff(resolve, reject) | |
| { | |
| //-- do what you want, resolve or reject the initial promise | |
| resolve('initial complete'); | |
| //reject('initial fail'); | |
| } | |
| //-- chained methods process. simply cycle through the parameters/arguments | |
| //-- if an async action takes place and a "promise" is returned the chain | |
| //-- will fire in sequence, bit cleaner than using a Deferred method | |
| function PromiseFactory() | |
| { | |
| for(var i=0; i<arguments.length; i++) | |
| { | |
| var value = arguments[i], | |
| self = this, | |
| funcarray = []; | |
| if(!value) | |
| { | |
| continue; | |
| } | |
| if( {}.toString.call(value) === '[object Function]' ) //-- check "success/failure" function combo | |
| { | |
| funcarray.push(_lame(value, this)); | |
| } | |
| else | |
| { | |
| for(var k=0; k<value.length; k++) | |
| { | |
| var subvalue = value[k]; | |
| if(subvalue) | |
| { | |
| funcarray.push(_lame(subvalue, this, k)); | |
| } | |
| } | |
| } | |
| this.methodpromise = this.methodpromise.then.apply(this.methodpromise, funcarray); | |
| } | |
| function _lame( value, context, index ) | |
| { | |
| return function() | |
| { | |
| if(!context.error) | |
| { | |
| if(index > 0) | |
| { | |
| context.error = true; | |
| } | |
| return value.apply(context, arguments); | |
| } | |
| //console.log('technically still firing'); | |
| }; | |
| } | |
| } | |
| //-- | |
| Initialize.prototype = | |
| { | |
| complete: function() | |
| { | |
| PromiseFactory.call(this, arguments); | |
| return this; | |
| }, | |
| amethod: function(before, after) | |
| { | |
| PromiseFactory.call(this, before, after); | |
| return this; | |
| } | |
| }; | |
| return new Initialize(); | |
| }; | |
| })(this); |
| <!doctype html> | |
| <html> | |
| <head> | |
| <meta charset="utf-8" /> | |
| <title>JS.Chaining & Native Promises</title> | |
| </head> | |
| <body> | |
| <div> | |
| <!-- Begin Body - - - - - - - - - - - - - - - - - - - - - - - - - - --> | |
| <h1>JS.Chaining & Native Promises</h1> | |
| <p> | |
| Sets out a pattern for chaining methods and implementing native promises alongside a polyfill for unsupported browsers. | |
| </p> | |
| <!-- End Body - - - - - - - - - - - - - - - - - - - - - - - - - - --> | |
| </div> | |
| <!-- | |
| https://github.com/jakearchibald/es6-promise#readme | |
| implement the polyfill for pretty much non Chrome, | |
| maybe Opera, and it seemed to be needed for Firefox 27 | |
| despite documentation to the contrary | |
| https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise | |
| --> | |
| <script> | |
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b(function(b,c){c(a)})}a.reject=b}),a("promise/resolve",["exports"],function(a){"use strict";function b(a){var b=this;return new b(function(b){b(a)})}a.resolve=b}),a("promise/utils",["exports"],function(a){"use strict";function b(a){return c(a)||"object"==typeof a&&null!==a}function c(a){return"function"==typeof a}function d(a){return"[object Array]"===Object.prototype.toString.call(a)}var e=Date.now||function(){return(new Date).getTime()};a.objectOrFunction=b,a.isFunction=c,a.isArray=d,a.now=e}),b("promise/polyfill").polyfill()}(); | |
| </script> | |
| <script src="chaining-and-native-promises.js"></script> | |
| <script> | |
| (function(window, undefined){ | |
| chainit() | |
| .complete( | |
| function(a) //-- resolution from the initial promise | |
| { | |
| debugger; | |
| return "first COMPLETE"; | |
| }, | |
| function(a) //-- rejection from the initial promise | |
| { | |
| debugger; | |
| }) | |
| .complete( | |
| function(a) //-- resolution | |
| { | |
| debugger; | |
| return new Promise(function(resolve, reject) | |
| { | |
| setTimeout(function() | |
| { | |
| resolve("second COMPLETE"); | |
| },1000); | |
| }); | |
| }, | |
| function(a) //-- rejection | |
| { | |
| debugger; | |
| }) | |
| .amethod( | |
| function(a) //-- do something | |
| { | |
| debugger; | |
| return "something complete"; | |
| }, | |
| function(a) //-- do another thing | |
| { | |
| debugger; | |
| return new Promise(function(resolve, reject) | |
| { | |
| setTimeout(function() | |
| { | |
| //resolve("fourth complete"); | |
| reject("fourth FAIL!"); //-- bit of a quirk, will find the next available "rejection" or "kinda" stop | |
| }, 3000); | |
| }); | |
| }) | |
| .amethod( | |
| function(a) //-- do something | |
| { | |
| debugger; | |
| return "something complete"; | |
| }, | |
| function(a) //-- do another thing | |
| { | |
| debugger; | |
| return new Promise(function(resolve, reject) | |
| { | |
| setTimeout(function() | |
| { | |
| reject("fifth FAIL!"); | |
| }, 3000); | |
| }); | |
| }) | |
| .complete( | |
| function(a) //-- resolution | |
| { | |
| debugger; | |
| return Promise.resolve("sixth complete, finished!"); | |
| }, | |
| function(a) //-- rejection | |
| { | |
| debugger; | |
| } | |
| ) | |
| .complete(function(a) //-- resolution | |
| { | |
| debugger; | |
| }); | |
| })(this); | |
| </script> | |
| </body> | |
| </html> |
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