Why accepting array<int> with type array<string> is considered unsafe?

[biozshock]

See https://phpstan.org/r/6670a1d9-a694-42a1-b678-b9765f28b9ee

<?php declare(strict_types = 1);

/**
 * @param string[] $y
 * @see \Doctrine\DBAL\Query\Expression\ExpressionBuilder::in
 */
function in($y): string
{
	return '';
}

in([1, 2]);

[ondrejmirtes]

Because int isn't a string obviously:

• https://phpstan.org/r/2f6e724b-4e9c-43ee-9c15-7cd742ee7a82
• https://3v4l.org/O7nUs