Hi together, as the voting for the "Type casting in array destructuring expressions" shows a clear direction to be declined (sad faces on my side, I really would've liked it as a feature completion of the casting feature set without the need for a really new syntax, as the parser also already coverred it, but ok, time to continue :D ), combined with a strong interest for the topic "type checks in array destructuring expressions" (as well in the discussion as in the vote) I've set up a first draft of an RFC covering this topic:
https://wiki.php.net/rfc/typehint_array_desctructuring The discussion around the casting in array destructuring brought up the idea to perform regular type checks in array destructuring expressions. This RFC proposes a new syntax to type hint a variable inside an array destructuring expression: $data = [42, 'Example', 2002]; [int $id, string $data, int $year] = $data; The type hints behave identically to the type hints used in method signatures (compare https://wiki.php.net/rfc/scalar_type_hints_v5). This especially includes a behaviour depending on the strict_types directive. Additionally to scalar type hints also object type hints are possible. I've not yet started an implementation draft but I think this one will be more tricky than the type cast implementation approach. As the parser re-uses the array definition for array destructuring expressions (which also leads to the type cast implementation without touching the parser) adding type hints to the definition would also affect other parts of the language eg. something like: $x = [int $a, string $b]; would be parsed by the parser. I'm currently not able to grasp the impact of such a change. But that's another topic. Let's focus on the idea itself instead of the implementation first. Thoughts on the first draft? Cheers, Enno -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
