29 lines
850 B
JavaScript
29 lines
850 B
JavaScript
'use strict';
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var atoa = require('atoa');
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var a = require('./a');
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var once = require('./once');
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var queue = require('./queue');
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var errored = require('./errored');
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var debounce = require('./debounce');
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var CONCURRENTLY = require('./CONCURRENTLY');
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module.exports = function concurrent (tasks, concurrency, done) {
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if (typeof concurrency === 'function') { done = concurrency; concurrency = CONCURRENTLY; }
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var d = once(done);
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var q = queue(worker, concurrency);
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var keys = Object.keys(tasks);
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var results = a(tasks) ? [] : {};
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q.unshift(keys);
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q.on('drain', function completed () { d(null, results); });
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function worker (key, next) {
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debounce(tasks[key], [proceed]);
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function proceed () {
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var args = atoa(arguments);
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if (errored(args, d)) { return; }
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results[key] = args.shift();
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next();
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}
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}
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};
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