55 lines
1.5 KiB
JavaScript
55 lines
1.5 KiB
JavaScript
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'use strict';
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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exports.default = compose;
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var _seq = require('./seq');
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var _seq2 = _interopRequireDefault(_seq);
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function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
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/**
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* Creates a function which is a composition of the passed asynchronous
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* functions. Each function consumes the return value of the function that
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* follows. Composing functions `f()`, `g()`, and `h()` would produce the result
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* of `f(g(h()))`, only this version uses callbacks to obtain the return values.
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*
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* If the last argument to the composed function is not a function, a promise
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* is returned when you call it.
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*
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* Each function is executed with the `this` binding of the composed function.
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*
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* @name compose
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* @static
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* @memberOf module:ControlFlow
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* @method
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* @category Control Flow
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* @param {...AsyncFunction} functions - the asynchronous functions to compose
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* @returns {Function} an asynchronous function that is the composed
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* asynchronous `functions`
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* @example
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*
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* function add1(n, callback) {
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* setTimeout(function () {
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* callback(null, n + 1);
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* }, 10);
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* }
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*
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* function mul3(n, callback) {
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* setTimeout(function () {
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* callback(null, n * 3);
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* }, 10);
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* }
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*
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* var add1mul3 = async.compose(mul3, add1);
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* add1mul3(4, function (err, result) {
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* // result now equals 15
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* });
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*/
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function compose(...args) {
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return (0, _seq2.default)(...args.reverse());
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}
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module.exports = exports['default'];
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