path: root/docs/ast/source/queue.js.json

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          "value": "*\n * A queue of tasks for the worker function to complete.\n * @typedef {Object} QueueObject\n * @property {Function} length - a function returning the number of items\n * waiting to be processed. Invoke with ().\n * @property {Function} started - a function returning whether or not any\n * items have been pushed and processed by the queue. Invoke with ().\n * @property {Function} running - a function returning the number of items\n * currently being processed. Invoke with ().\n * @property {Function} workersList - a function returning the array of items\n * currently being processed. Invoke with ().\n * @property {Function} idle - a function returning false if there are items\n * waiting or being processed, or true if not. Invoke with ().\n * @property {number} concurrency - an integer for determining how many `worker`\n * functions should be run in parallel. This property can be changed after a\n * `queue` is created to alter the concurrency on-the-fly.\n * @property {Function} push - add a new task to the `queue`. Calls `callback`\n * once the `worker` has finished processing the task. Instead of a single task,\n * a `tasks` array can be submitted. The respective callback is used for every\n * task in the list. Invoke with (task, [callback]),\n * @property {Function} unshift - add a new task to the front of the `queue`.\n * Invoke with (task, [callback]).\n * @property {Function} saturated - a callback that is called when the number of\n * running workers hits the `concurrency` limit, and further tasks will be\n * queued.\n * @property {Function} unsaturated - a callback that is called when the number\n * of running workers is less than the `concurrency` & `buffer` limits, and\n * further tasks will not be queued.\n * @property {number} buffer - A minimum threshold buffer in order to say that\n * the `queue` is `unsaturated`.\n * @property {Function} empty - a callback that is called when the last item\n * from the `queue` is given to a `worker`.\n * @property {Function} drain - a callback that is called when the last item\n * from the `queue` has returned from the `worker`.\n * @property {Function} error - a callback that is called when a task errors.\n * Has the signature `function(error, task)`.\n * @property {boolean} paused - a boolean for determining whether the queue is\n * in a paused state.\n * @property {Function} pause - a function that pauses the processing of tasks\n * until `resume()` is called. Invoke with ().\n * @property {Function} resume - a function that resumes the processing of\n * queued tasks when the queue is paused. Invoke with ().\n * @property {Function} kill - a function that removes the `drain` callback and\n * empties remaining tasks from the queue forcing it to go idle. Invoke with ().\n ",
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      "value": "*\n * A queue of tasks for the worker function to complete.\n * @typedef {Object} QueueObject\n * @property {Function} length - a function returning the number of items\n * waiting to be processed. Invoke with ().\n * @property {Function} started - a function returning whether or not any\n * items have been pushed and processed by the queue. Invoke with ().\n * @property {Function} running - a function returning the number of items\n * currently being processed. Invoke with ().\n * @property {Function} workersList - a function returning the array of items\n * currently being processed. Invoke with ().\n * @property {Function} idle - a function returning false if there are items\n * waiting or being processed, or true if not. Invoke with ().\n * @property {number} concurrency - an integer for determining how many `worker`\n * functions should be run in parallel. This property can be changed after a\n * `queue` is created to alter the concurrency on-the-fly.\n * @property {Function} push - add a new task to the `queue`. Calls `callback`\n * once the `worker` has finished processing the task. Instead of a single task,\n * a `tasks` array can be submitted. The respective callback is used for every\n * task in the list. Invoke with (task, [callback]),\n * @property {Function} unshift - add a new task to the front of the `queue`.\n * Invoke with (task, [callback]).\n * @property {Function} saturated - a callback that is called when the number of\n * running workers hits the `concurrency` limit, and further tasks will be\n * queued.\n * @property {Function} unsaturated - a callback that is called when the number\n * of running workers is less than the `concurrency` & `buffer` limits, and\n * further tasks will not be queued.\n * @property {number} buffer - A minimum threshold buffer in order to say that\n * the `queue` is `unsaturated`.\n * @property {Function} empty - a callback that is called when the last item\n * from the `queue` is given to a `worker`.\n * @property {Function} drain - a callback that is called when the last item\n * from the `queue` has returned from the `worker`.\n * @property {Function} error - a callback that is called when a task errors.\n * Has the signature `function(error, task)`.\n * @property {boolean} paused - a boolean for determining whether the queue is\n * in a paused state.\n * @property {Function} pause - a function that pauses the processing of tasks\n * until `resume()` is called. Invoke with ().\n * @property {Function} resume - a function that resumes the processing of\n * queued tasks when the queue is paused. Invoke with ().\n * @property {Function} kill - a function that removes the `drain` callback and\n * empties remaining tasks from the queue forcing it to go idle. Invoke with ().\n ",
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      "value": "*\n * Creates a `queue` object with the specified `concurrency`. Tasks added to the\n * `queue` are processed in parallel (up to the `concurrency` limit). If all\n * `worker`s are in progress, the task is queued until one becomes available.\n * Once a `worker` completes a `task`, that `task`'s callback is called.\n *\n * @name queue\n * @static\n * @memberOf async\n * @category Control Flow\n * @param {Function} worker - An asynchronous function for processing a queued\n * task, which must call its `callback(err)` argument when finished, with an\n * optional `error` as an argument.  If you want to handle errors from an\n * individual task, pass a callback to `q.push()`. Invoked with\n * (task, callback).\n * @param {number} [concurrency=1] - An `integer` for determining how many\n * `worker` functions should be run in parallel.  If omitted, the concurrency\n * defaults to `1`.  If the concurrency is `0`, an error is thrown.\n * @returns {QueueObject} A queue object to manage the tasks. Callbacks can\n * attached as certain properties to listen for specific events during the\n * lifecycle of the queue.\n * @example\n *\n * // create a queue object with concurrency 2\n * var q = async.queue(function(task, callback) {\n *     console.log('hello ' + task.name);\n *     callback();\n * }, 2);\n *\n * // assign a callback\n * q.drain = function() {\n *     console.log('all items have been processed');\n * };\n *\n * // add some items to the queue\n * q.push({name: 'foo'}, function(err) {\n *     console.log('finished processing foo');\n * });\n * q.push({name: 'bar'}, function (err) {\n *     console.log('finished processing bar');\n * });\n *\n * // add some items to the queue (batch-wise)\n * q.push([{name: 'baz'},{name: 'bay'},{name: 'bax'}], function(err) {\n *     console.log('finished processing item');\n * });\n *\n * // add some items to the front of the queue\n * q.unshift({name: 'bar'}, function (err) {\n *     console.log('finished processing bar');\n * });\n ",
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