async/lib/compose.js at gh-pages · againksy/async

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import seq from './seq';

import rest from './internal/rest';

/**

* Creates a function which is a composition of the passed asynchronous

* functions. Each function consumes the return value of the function that

* follows. Composing functions `f()`, `g()`, and `h()` would produce the result

* of `f(g(h()))`, only this version uses callbacks to obtain the return values.

* Each function is executed with the `this` binding of the composed function.

* @name compose

* @static

* @memberOf module:ControlFlow

* @method

* @category Control Flow

* @param {...Function} functions - the asynchronous functions to compose

* @returns {Function} an asynchronous function that is the composed

* asynchronous `functions`

* @example

* function add1(n, callback) {

* setTimeout(function () {

* callback(null, n + 1);

* }, 10);

* }

* function mul3(n, callback) {

* setTimeout(function () {

* callback(null, n * 3);

* }, 10);

* }

* var add1mul3 = async.compose(mul3, add1);

* add1mul3(4, function (err, result) {

* // result now equals 15

* });

export default rest(function(args) {

return seq.apply(null, args.reverse());

});