Re: [RFC] clamp

czw., 24 cze 2021 o 02:15 tyson andre <tysonandre775@hotmail.com> napisał(a): > Hello Kim Hallberg, > > > The RFC for the clamp function is now open and under discussion, you now > have 2 weeks > > to discuss, suggest improvements and open issues before voting is > considered. > > > From https://wiki.php.net/rfc/clamp - > > > Current userland implementations are handled in several ways, some of > which use min and max to check the bound, > > which is costly and slow when called often. > > Because userland implementations are for the most part not > cost-effective when called multiple times, > > a language implementation is desired. > > I'd strongly prefer an actual benchmark for context and accuracy - is it > actually faster or slower than the most efficient userland implementation > and by how much? > E.g. in an optimized NTS build with CFLAGS=-O2, opcache > enabled(zend_extension=opcache, opcache.enable=1,opcache.enable_cli=1), > and no debug configure flags, how many calls per second can be made on > variable values of $num for both? > (I'd assume over twice as fast as calling both min/max from another > function, but possibly slower than efficient_clamp, but haven't run this) > > For userland implementations that did use min/max, they probably weren't > performance sensitive for the application. > > ```php > function efficient_clamp(int|float $num, int|float $min, int|float $max): > int|float { > return $num < $min ? $min : ($num > $max ? $max : $num); > } > ``` > Do we really need it? IMO the performance of this is not gonna change anything much. We're talking about nanoseconds here possibly. I'm looking forward to Hello World RFC - that's also often implemented in userland. ```php function hello(?string $who = 'World', bool $return = false, bool $newline = true): ?string { $str = "Hello {$who}!" . ($newline ? PHP_EOL : ''); if ($return) return $str; echo $str; } ``` I get an impression that we constantly add things into standard library which are from a language perspective irrelevant and that all could be developed in userland with no harm. Cheers, -- Michał Marcin Brzuchalski