Re: [RFC] [PRE-VOTE] Union types

On 06/03/2016 10:16 AM, Jordi Boggiano wrote:

On 03/06/2016 15:58, Thomas Bley wrote:

To me type declarations help to make my code easier and more consistent. Having multiple scalar types for a single function parameter is against this goal since I need extra logic to handle this. e.g. function foo(string | int | bool $bar) {} makes no sense in weak mode since string can already handle int, bool, float, etc. having different behavior between foo("42"); function foo(string $b) {echo gettype($b);} // string and foo("42"); function foo(string | int $b) {echo gettype($b);} // integer also makes no sense to me. Things like string|array are useful (e.g. str_replace) since we can cast the string easily to array and calling a string parameter with an array would give a fatal error.

That is a useful case, and don't forget also return values, e.g. all the XX|false-kind of return types it's also nice to have. I don't think for function arguments it's massively useful and I doubt it'll get put everywhere, but it's nice to be able to express this when you have to. Cheers

For parameters, I really don't think | is going to be the common use case. (It should still be rational, but I don't expect to see it day to day.) InterfaceA & InterfaceB Is the more useful use case for parameters. | is, as noted, likely more useful on returns. (even though I would discourage their use in most cases for reasons I won't go into here). --Larry Garfield