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]
