optionalifPresentv

optionalifPresentv is a function concept found in some programming libraries that operate on optional or maybe values. It takes two arguments: an optional value of type Optional<T> (or a similar container) and a visitor function that consumes a T. If the optional contains a value, optionalifPresentv invokes the visitor with that value and returns a boolean indicating that a value was present. If the optional is empty, it performs no action and returns false.

The primary purpose of optionalifPresentv is to enable conditional execution of side effects without explicit presence checks. By abstracting the presence test, it supports concise, fluent code paths where an action should only occur when a value exists. The function is typically generic over the contained type, allowing it to be used with any value type supported by the language’s optional construct. Return values, when defined, commonly convey whether a value was processed, which can aid in chaining or control flow.

Usage patterns usually resemble applying a small side effect such as logging, formatting, or triggering a downstream action only when a value is present. The visitor function is responsible for what happens with the value; optionalifPresentv itself does not alter or transform the value, beyond reporting the presence.

Edge cases include ensuring that the visitor’s execution is the only side effect and that exceptions thrown by the visitor propagate to the caller. In languages with rich option/type systems, optionalifPresentv often coexists with other helpers such as map, filter, or unwrap methods.

See also: Optional, Option, ifPresent.