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.

indexWhere(Array<T>, (item: T) -> Boolean): Number

Returns the index of the first occurrence of an element that matches a condition within the array.

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 returns the index of the value from the input array that matches the condition in the lambda expression, (item) → item startsWith "Jul".


%dw 2.0
import * from dw::core::Arrays
output application/json
var users = ["Mariano", "Leandro", "Julian"]
users indexWhere (item) -> item startsWith "Jul"



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