`lastIndexWhere()`

Get the index of the last array element that matches the predicate.

Signature

lastIndexWhere(predicate: () => Boolean | Null): Number | Null

lastIndexWhere(predicate: () => Boolean | Null, end: Number): Number | Null

The lastIndexWhere() method returns the array index of the element that matches the predicate.

Parameter	Type	Required	Description
predicate	Function	Yes	Function to search for a matching element.
end	Function		Search right-to-left for a match beginning at end, inclusive.

Parameter

Type

Required

Description

predicate

Yes

Function to search for a matching element.

end

Search right-to-left for a match beginning at end, inclusive.

Type Description

Type	Description
Number	Index of element that matches predicate or `null` if a match isn’t found.

Index of element that matches predicate or null if a match isn’t found.

['a', 'b', 'c', 'b'].lastIndexWhere(v => v == 'b')

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