Re: Apply strict_types to internal functions

On 29/08/2023 01:46, Saki Takamachi wrote:

As the documentation below states, PHP's internal functions currently ignore strict_types. https://www.php.net/manual/en/language.types.declarations.php#language.types.declarations.strict

Just to be really clear, it is not true that internal functions "ignore" the setting; they behave exactly the same as any userland function which was *declared* in strict_types=0 mode. The warning in the manual is actually a consequence of the following Note (perhaps the order should be reversed?): 1. Strict typing applies to function calls made from within the file with strict typing enabled 2. Function calls from within internal functions will not be affected by the |strict_types| declaration To clarify the scenario, imagine three files: /* a.php */ declare(strict_types=0); function call_me_back(callable $f, mixed $input) {

    $f($input);

} /* b.php */ declare(strict_types=1); function output_me(string $output) {

    echo "$output\n";

} /* c.php */ declare(strict_types=1); call_me_back( output_me(...), 42 ); The only calls that happen are: 1. A call from c.php to call_me_back; c.php is in strict_types=1 mode, so the parameters $f and $input will not be coerced 2. A call from a.php to output_me; a.php is in strict_types=0 mode, so the parameter $output *will* be coerced to a string The behaviour of internal functions like array_filter is exactly the same - array_filter is  the caller, and it is defined in strict_types=0 mode, just like call_me_back above; the mode set in any other code is irrelevant, because it is not the caller. As Claude Pache, it's actually very difficult to design a version of the feature that would be fully intuitive in this case - if I write the below, does the caller of wrapped_array_filter still get to control the mode that call_me_back is run under? function call_me_back(int $value) {

    return $value <= 42;

} function backwards_array_filter(array $array, ?callable $callback = null, int $mode = 0): array {

    return array_reverse(   array_filter($array, $callback, $mode)   );

} // In another file: var_dump( backwards_array_filter($some_array, call_me_back(...)) ); Regards, -- Rowan Tommins [IMSoP]