Re: [RFC] Scalar Type Hinting With Casts (re-opening)

On 16 Jul 2014, at 20:47, Rowan Collins <rowan.collins@gmail.com> wrote: > I think this would be quite nice - keeps things relatively short without introducing so much > punctuation that it starts looking like a Perl script ;) > > The only problem is that either you need a whole set of functions (safe_int($foo), > safe_float($foo), etc) or you need some format for that second argument, which gets you into some > odd meta-validation: if you take a string, or an integer (expected to be in the form of a constant > like PHP_INT), then it would be possible to write safe_cast($foo, $bar), and now we need rules on > validating $bar, and what happens if it's wrong. > > The magic form with a keyword like you've written avoids that, but it feels kind of weird > - like when SQL date functions take things like "day" and "hour" as barewords > rather than strings. Perhaps this could work? if (safe_cast((int!)$foobar)) { $foobar = (int!)$foobar; } else { $foobar = 1; } With safe_cast() being a pseudo-function à la isset() et al. I’m not really sure adding a new set of safe casts is really such a good idea; we don’t really need (int!) even, we could just have can_cast_int_strict (or something like that) given that (int) and (int!) do the same thing for the non-failure cases. And perhaps it’d be better just to leave this to scalar type hints, I’m not sure I really want to add this stuff... -- Andrea Faulds http://ajf.me/