blob: eb9abe576d375de18df3a5dfd1a289b5cf674329 [file] [log] [blame]
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = compose;
var _seq = require('./seq');
var _seq2 = _interopRequireDefault(_seq);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/**
* 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.
*
* If the last argument to the composed function is not a function, a promise
* is returned when you call it.
*
* Each function is executed with the `this` binding of the composed function.
*
* @name compose
* @static
* @memberOf module:ControlFlow
* @method
* @category Control Flow
* @param {...AsyncFunction} 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
* });
*/
function compose(...args) {
return (0, _seq2.default)(...args.reverse());
}
module.exports = exports['default'];