maybeIfPresentx

maybeIfPresentx is a term used in programming discussions to describe a conditional transformation pattern applied to optional values. It represents a function or utility that, given an optional or Maybe value and a function, applies the function to the contained value if it exists and returns an optional containing the result; if the value is absent, it returns an empty optional. The “x” in the name often signals an extended or cross-language variant, or serves as a project-specific naming convention, not a standardized keyword.

Definition: For an Optional<A> opt and a function f: A -> B, maybeIfPresentx(opt, f) yields Optional<B>. Equivalently in languages with Maybe: maybeIfPresentx(maybeValue, f) -> Maybe<B>.

Behavior: If opt has a value v, returns Just f(v) or Some f(v). If opt is empty, returns empty.

Examples: maybeIfPresentx(Optional.of(5), v -> v * 2) -> Optional.of(10). maybeIfPresentx(Optional.empty(), v -> v * 2) -> Optional.empty().

Applications: used to express conditional mapping without explicit existence checks; helps chain transformations on optional values and integrate with other optional-based combinators like map, flatMap, and filter.

Comparison: similar to map on Option/Optional, but some variants may perform side effects or return different container types; “ifPresent” typically performs side effects and returns unit, whereas maybeIfPresentx returns a transformed optional.

History and usage: not a standard language feature; encountered in tutorials, libraries, or codebases exploring optional handling patterns. See also: Optional, Maybe, map, flatMap, ifPresent.