# Continuable-fantasy Turn the awesome [continuable][cont] into a [fantasy land][fantasy] compliant functor and monad. Since it is based of [continuable][cont] any error will short circuit the chain and propagate all the way to the end. The Fantasy-land spec lets you use the very familiar `.map()` function on any compliant type, and sometimes more. // -- List -- var arr = Array('Hello world') // => array with one item ('Hello world') arr.map(function(s) { return s.toUpperCase() }) // => new array with one item ('HELLO WORLD') // -- Async -- var later = ContinuableFantasy.of('Hello world') // => function that will be called with (null, 'Hello world') later.map(function(s) { return s.toUpperCase() }) // => new function that will be called with (null, 'HELLO WORLD') ## Example var buffer = ContinuableFantasy(fs.readFile.bind(null, './simple.js')) // Make the buffer a string buffer.map(String) // Take only first line .map(function(str) { return str.split('\n')[0] }) // Consume the error or result .consume(handleError, console.log) // (function(err, data) { // if (err) return handleError(err); // console.log(val) // }) // Is ok too, if you prefer that. It's just callbacks under the hood function handleError(err) { console.log(err) // Not that handled, but you get the point } ## Docs // type Continuable: (Error, Value) => void ### Extender/Decorator #### ` ContinuableFantasy( Continuable ) => contFantasy ` var contBuffer = fs.readFile.bind(null, 'fileName') // Extends contBuffer with map, chain and consume ContinuableFantasy(contBuffer) ### Instanse methods #### ` contFantasy.map( func:(A) => B ) => contFantasy ` contFantasy.map(function(buffer) { return buffer.toString() }) // => contFantasy #### ` contFantasy.chain( func:(A) => contFantasy ) => `contFanasy contFantasy.chain(function(str) { var json = JSON.parse(str) // The data from the old continuable is used to determine the new return ContinuableFantasy(fs.readFile.bind(null, json.property)) }) // => contFantasy #### ` contFantasy.consume( (Error) => void, (A) => void ) => void ` contFantasy.consume( function(error) { console.log('There was an error') console.log(error) }, function(string) // String ready for usage console.log(string) ) ### Static methods #### ` ContinuableFantasy.of( Value ) => contFantasy ` ContinuableFantasy.of( 'Hello' ).consume(null, function(s) { assert.equal(s, 'Hello') }) #### ` ContinuableFantasy.error( Error ) => contFantasy ` var error = new Error('Bad bad thing, do not throw in node') ContinuableFantasy.error( err ).consume(function(err) { assert.equal(err, error) }) // Did not handle success #### ` ContinuableFantasy.join( Continuable> ) => contFantasy ` var contOfA = ContinuableFantasy.of('So nested') var contOfContOfA = ContinuableFantasy.of(contOfA) ContinuableFantasy.join(contOfContOfA) .consume(null, function(s) { assert.equal(s, 'So nested') }) ## Fantasy Land Compatible [![](https://raw.github.com/pufuwozu/fantasy-land/master/logo.png) ](https://github.com/pufuwozu/fantasy-land) ## License MIT [cont]: https://npmjs.org/package/continuable [fantasy]: https://github.com/puffnfresh/fantasy-land

continuable-fantasy