DataWeave 2.2 is compatible and bundled with Mule 4.2. Standard Support for Mule 4.2 ended on May 2, 2021, and this version of Mule will reach its End of Life on May 2, 2023, when Extended Support ends.

Deployments of new applications to CloudHub that use this version of Mule are no longer allowed. Only in-place updates to applications are permitted.

MuleSoft recommends that you upgrade to the latest version of Mule 4 that is in Standard Support so that your applications run with the latest fixes and security enhancements.

takeWhile(Array<T>, (item: T) -> Boolean): Array<T>

Selects elements from the array while the condition is met but stops the selection process when it reaches an element that fails to satisfy the condition.

To select all elements that meet the condition, use the filter function.

Introduced in DataWeave 2.2.0. Supported by Mule 4.2 and later.


Name Description


The array of elements.


The condition (or expression) used to match an element in the array.


This example iterates over the elements in the array and selects only those where the index is <= 2. Note that it stops selecting elements when it reaches an element that is greater than 2. It does not select the second 1 because 4 precedes 1 in the array. The function outputs the result into an array.


%dw 2.0
import * from dw::core::Arrays
output application/json
var arr = [0,1,2,4,1]
arr takeWhile $ <= 2



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