mapIndexed()
Perform a mapping operation given the element being mapped and its zero-based index
Implementation Notes
Signature
mapIndexed(BiFunction<Integer, INPUT, OUTPUT> mappingFunction)
- mappingFunction- A non-null function to convert input elements and their indexes to output elements.
Examples
Map with index
Stream
    .of("A", "B", "C", "D")
    .gather(
        Gatherers4j.mapIndexed(
            (index, element) -> element + index
        )
     )
     .toList();
// [A0 B1 C2 D3]