> For the complete documentation index, see [llms.txt](https://boxlang.ortusbooks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/async/asyncallapply.md). # AsyncAllApply This function can accept an array of items or a struct of items and apply a function to each of the item's in parallel. The `mapper` argument receives the appropriate item and must return a result. The \`errorHandler\` is optional and will be called if the mapper function throws an exception. The error handler receives the exception and the item that caused it, allowing you to handle errors gracefully. The result is a future that will return an array of results, or a struct of results if the input was a struct. The \`executor\` argument is optional and allows you to specify a custom executor for the asynchronous operations. If not provided, the common fork-join pool will be used. The \`timeout\` and \`timeUnit\` arguments allow you to specify a timeout for the operation. If the operation does not complete within the specified timeout, it will throw a TimeoutException. The allowed time units are: \`DAYS\`, \`HOURS\`, \`MINUTES\`, \`SECONDS\`, \`MILLISECONDS\`, \`MICROSECONDS\`, \`NANOSECONDS\`. Example usage: ``` // Array allApply( items, ( item ) => item.getMemento() ) // Struct: The result object is a struct of `key` and `value` allApply( data, ( item ) => item.key & item.value.toString() ) ``` ## Method Signature ``` AsyncAllApply(items=[any], mapper=[function], errorHandler=[function], executor=[any], timeout=[long], timeUnit=[any]) ``` ### Arguments | Argument | Type | Required | Description | Default | | -------------- | ---------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------- | | `items` | `any` | `true` | The items to apply the function to. Can be an array or a struct. | | | `mapper` | `function` | `true` | The function to apply to each item. It receives the item as an argument and must return a result. | | | `errorHandler` | `function` | `false` | Optional function to handle errors. It receives the exception and the item that caused it. | | | `executor` | `any` | `false` | Optional executor to use for the asynchronous operations. If not provided, the common fork-join pool will be used. | | | `timeout` | `long` | `false` | Optional timeout for the operation. If the operation does not complete within this time, it will throw a TimeoutException. | `0` | | `timeUnit` | `any` | `false` | Optional time unit for the timeout. Defaults to seconds. Allowed values are: `DAYS`, `HOURS`, `MINUTES`, `SECONDS`, `MILLISECONDS`, `MICROSECONDS`, `NANOSECONDS`. | `SECONDS` | ## Examples ### Apply a function to each item in parallel Accepts an array of items and a function, applying the function to each item in parallel. ```java items = [ 1, 2, 3, 4, 5 ]; results = allApply( items, ( n ) => n * n ).get(); writeOutput( results.toString() ); ``` Result: \[1, 4, 9, 16, 25] ### Process a struct of items ```java data = { a: 10, b: 20, c: 30 }; results = allApply( data, ( v ) => v * 2 ).get(); writeOutput( results.len() ); ``` Result: 3 ### Using a named executor ```java executorNew( "myPool", "fixed", 4 ); results = allApply( [ 1, 2, 3 ], ( n ) => n + 1, "myPool" ).get(); writeOutput( results.toString() ); ``` Result: \[2, 3, 4] ## Related * [AsyncAll](/boxlang-language/reference/built-in-functions/async/asyncall.md) * [AsyncAny](/boxlang-language/reference/built-in-functions/async/asyncany.md) * [AsyncRun](/boxlang-language/reference/built-in-functions/async/asyncrun.md) * [ExecutorDelete](/boxlang-language/reference/built-in-functions/async/executordelete.md) * [ExecutorGet](/boxlang-language/reference/built-in-functions/async/executorget.md) * [ExecutorHas](/boxlang-language/reference/built-in-functions/async/executorhas.md) * [ExecutorList](/boxlang-language/reference/built-in-functions/async/executorlist.md) * [ExecutorNew](/boxlang-language/reference/built-in-functions/async/executornew.md) * [ExecutorShutdown](/boxlang-language/reference/built-in-functions/async/executorshutdown.md) * [ExecutorStatus](/boxlang-language/reference/built-in-functions/async/executorstatus.md) * [FutureNew](/boxlang-language/reference/built-in-functions/async/futurenew.md) * [IsInThread](/boxlang-language/reference/built-in-functions/async/isinthread.md) * [isThreadAlive](/boxlang-language/reference/built-in-functions/async/isthreadalive.md) * [IsThreadInterrupted](/boxlang-language/reference/built-in-functions/async/isthreadinterrupted.md) * [RunAsync](/boxlang-language/reference/built-in-functions/async/runasync.md) * [ThreadCurrent](/boxlang-language/reference/built-in-functions/async/threadcurrent.md) * [ThreadInterrupt](/boxlang-language/reference/built-in-functions/async/threadinterrupt.md) * [ThreadJoin](/boxlang-language/reference/built-in-functions/async/threadjoin.md) * [ThreadNew](/boxlang-language/reference/built-in-functions/async/threadnew.md) * [ThreadTerminate](/boxlang-language/reference/built-in-functions/async/threadterminate.md) --- # Agent Instructions This documentation is published with GitBook. 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