IndexOf function

Fully qualified name: Std.Arrays.IndexOf

function IndexOf<'T>(predicate : ('T -> Bool), array : 'T[]) : Int

Summary

Returns the first index of the first element in an array that satisfies a given predicate. If no such element exists, returns -1.

Input

predicate

A predicate function acting on elements of the array.

array

An array to be searched using the given predicate.

Output

Either the smallest index of an element for which predicate(array[index]) is true, or -1 if no such element exists.

Example

The following code gets the index of the first even number in the input array.

let indexOfFirstEven = IndexOf(x -> x % 2 == 0, [1, 3, 17, 2, 21]);
// `indexOfFirstEven` is 3.