map

map(target, map)

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

data-first

map(5, (x) => x * 2); // 10
map(null, (x) => x * 2); // null
map(undefined, (x) => x * 2); // undefined

data-last

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

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