Re: [RFC] [Discussion] Add clamp function

Hi Am 2025-08-28 08:35, schrieb Hans Krentel:

This also highlights a minor but important clarification for the documentation. To make the behavior perfectly unambiguous, I suggest a small edit to explicitly state the bounds are inclusive.

This is a good point and I agree that it should be spelled out explicitly. However to me this also raises the question if the interval boundaries should be configurable to switch between closed intervals and (half-)open intervals. For many applications of continuous values a right-open interval (excluding the upper boundary) is more useful, since this makes it easy to generate non-overlapping ranges (e.g. to clamp to a given day when passing DateTimeImmutable). This would also provide an additional value-add over the min-max construction, where the boundaries would need to be calculated manually, which is super complicated to do in userland for floats. There's precedent in ext/random with the Randomizer::getFloat() method that takes a Random\IntervalBoundary enum to decide on the the interpretation of the boundary values. Translated to clamp() this could mean:

    $value = 1.0;
    clamp($value, 0.0, 1.0, IntervalBoundary::ClosedOpen); // 0.999999999999999888978

Best regards Tim Düsterhus