mapOrElse

mapOrElse(target, map, orElse)

Applies a mapping function to a value if it's not null or undefined, otherwise calls a fallback function. If the target value is null or undefined, it calls the orElse function and returns its result. Otherwise, it applies the mapping function and returns the result.

data-first

mapOrElse(
    5,
    (x) => x * 2,
    () => 0,
); // 10

mapOrElse(
    null,
    (x) => x * 2,
    () => 0,
); // 0

mapOrElse(
    undefined,
    (x) => x * 2,
    () => -1,
); // -1

data-last

pipe(
    5,
    mapOrElse(
        (x) => x * 2,
        () => 0,
    ),
); // 10

pipe(
    null,
    mapOrElse(
        (x) => x * 2,
        () => 0,
    ),
); // 0