Async
Related Docs:
trait Async
| package async
Applies the provided arguments to each function in the array, calling callback after all functions have completed.
Applies the provided arguments to each function in the array, calling callback after all functions have completed. If you only provide the first argument, then it will return a function which lets you pass in the arguments as if it were a single function call.
A collection of asynchronous functions to all call with the same arguments
any number of separate arguments to pass to the function
the final argument should be the callback, called when all functions have completed processing
Creates a function which is a composition of the passed asynchronous functions.
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.
the asynchronous functions to compose
compose(fn1, fn2...)
Applies the function iteratee to each item in coll, in parallel.
Applies the function iteratee to each item in coll, in parallel. The iteratee is called with an item from the list, and a callback for when it has finished. If the iteratee passes an error to its callback, the main callback (for the each function) is immediately called with the error.
Note, that since this function applies iteratee to each item in parallel, there is no guarantee that the iteratee functions will complete in order.
A collection to iterate over.
A function to apply to each item in coll. The iteratee is passed a callback(err) which must be called once it has completed. If no error has occurred, the callback should be run without arguments or with an explicit null argument. The array index is not passed to the iteratee. If you need the index, use forEachOf.
An optional callback which is called when all iteratee functions have finished, or an error occurs.
Applies the function iteratee to each item in coll, in parallel.
Applies the function iteratee to each item in coll, in parallel. The iteratee is called with an item from the list, and a callback for when it has finished. If the iteratee passes an error to its callback, the main callback (for the each function) is immediately called with the error.
Note, that since this function applies iteratee to each item in parallel, there is no guarantee that the iteratee functions will complete in order.
A collection to iterate over.
the limit
A function to apply to each item in coll. The iteratee is passed a callback(err) which must be called once it has completed. If no error has occurred, the callback should be run without arguments or with an explicit null argument. The array index is not passed to the iteratee. If you need the index, use forEachOf.
Optional A callback which is called when all iteratee functions have finished, or an error occurs.
Applies the function iteratee to each item in coll, in parallel.
Applies the function iteratee to each item in coll, in parallel. The iteratee is called with an item from the list, and a callback for when it has finished. If the iteratee passes an error to its callback, the main callback (for the each function) is immediately called with the error.
Note, that since this function applies iteratee to each item in parallel, there is no guarantee that the iteratee functions will complete in order.
A collection to iterate over.
A function to apply to each item in coll. The iteratee is passed a callback(err) which must be called once it has completed. If no error has occurred, the callback should be run without arguments or with an explicit null argument. The array index is not passed to the iteratee. If you need the index, use forEachOf.
An optional callback which is called when all iteratee functions have finished, or an error occurs.
Returns a new array of all the values in coll which pass an async truth test.
Returns a new array of all the values in coll which pass an async truth test. This operation is performed in parallel, but the results array will be in the same order as the original.
A collection to iterate over.
iteratee(item, callback) - A truth test to apply to each item in coll. The iteratee is passed a callback(err, truthValue) , which must be called with a boolean argument once it has completed. Callback arguments changed in 2.0
callback(err, results) - Optional A callback which is called after all the iteratee functions have finished.
Like each, except that it passes the key (or index) as the second argument to the iteratee.
Like each, except that it passes the key (or index) as the second argument to the iteratee.
A collection to iterate over.
iteratee(item, key, callback) - A function to apply to each item in coll. The key is the item's key, or index in the case of an array. The iteratee is passed a callback(err) which must be called once it has completed. If no error has occurred, the callback should be run without arguments or with an explicit null argument.
callback(err) - An optional callback which is called when all iteratee functions have finished, or an error occurs.
forEachOf(coll, iteratee, [callback])
Produces a new collection of values by mapping each value in coll through the iteratee function.
Produces a new collection of values by mapping each value in coll through the iteratee function. The iteratee is called with an item from coll and a callback for when it has finished processing. Each of these callback takes 2 arguments: an error, and the transformed item from coll. If iteratee passes an error to its callback, the main callback (for the map function) is immediately called with the error.
A collection to iterate over.
iteratee(item, callback) - A function to apply to each item in coll. The iteratee is passed a callback(err, transformed) which must be called once it has completed with an error (which can be null) and a transformed item.
callback(err, results) - Optional A callback which is called when all iteratee functions have finished, or an error occurs. Results is an array of the transformed items from the coll.
Run the tasks collection of functions in parallel, without waiting until the previous function has completed.
Run the tasks collection of functions in parallel, without waiting until the previous function has completed. If any of the functions pass an error to its callback, the main callback is immediately called with the value of the error. Once the tasks have completed, the results are passed to the final callback as an array.
A collection containing functions to run. Each function is passed a callback(err, result) which it must call on completion with an error err (which can be null) and an optional result value.
callback(err, results) - An optional callback to run once all the functions have completed successfully. This function gets a results array (or object) containing all the result arguments passed to the task callbacks.
Creates a queue object with the specified concurrency.
Creates a queue object with the specified concurrency. Tasks added to the queue are processed in parallel (up to the concurrency limit). If all workers are in progress, the task is queued until one becomes available. Once a worker completes a task, that task's callback is called.
An asynchronous function for processing a queued task, which must call its callback(err) argument when finished, with an optional error as an argument. If you want to handle errors from an individual task, pass a callback to q.push(). Invoked with (task, callback).
An integer for determining how many worker functions should be run in parallel. If omitted, the concurrency defaults to 1. If the concurrency is 0, an error is thrown.
A queue object to manage the tasks. Callbacks can attached as certain properties to listen for specific events during the lifecycle of the queue.
The opposite of filter.
The opposite of filter. Removes values that pass an async truth test.
A collection to iterate over.
iteratee(item, callback) - A truth test to apply to each item in coll. The iteratee is passed a callback(err, truthValue) , which must be called with a boolean argument once it has completed. Callback arguments changed in 2.0
callback(err, results) - Optional A callback which is called after all the iteratee functions have finished.
reject(coll, iteratee, [callback])
Version of the compose function that is more natural to read.
Version of the compose function that is more natural to read. Each function consumes the return value of the previous function. It is the equivalent of compose with the arguments reversed.
Each function is executed with the this binding of the composed function.
the asynchronous functions to compose
seq(fn1, fn2...)
Calls callback on a later loop around the event loop.
Calls callback on a later loop around the event loop. In Node.js this just calls setImmediate. In the browser it will use setImmediate if available, otherwise setTimeout(callback, 0), which means other higher priority events may precede the execution of callback.
This is used internally for browser-compatibility purposes.
The function to call on a later loop around the event loop.
any number of additional arguments to pass to the callback on the next tick
Runs the tasks array of functions in series, each passing their results to the next in the array.
Runs the tasks array of functions in series, each passing their results to the next in the array. However, if any of the tasks pass an error to their own callback, the next function is not executed, and the main callback is immediately called with the error.
An array of functions to run, each function is passed a callback(err, result1, result2, ...) it must call on completion. The first argument is an error (which can be null) and any further arguments will be passed as arguments in order to the next task.
An optional callback to run once all the functions have completed. This will be passed the results of the last task's callback (e.g. callback(err, [results])).
Async is a utility module which provides straight-forward, powerful functions for working with asynchronous JavaScript. Although originally designed for use with Node.js and installable via
npm install --save async, it can also be used directly in the browser.2.0.1
http://caolan.github.io/async/