Create a filter function by assembling the factory function as PHP code and eval

filter.php

<?php

define('FILTER_MATCH_EXACT', 1 << 0);
define('FILTER_MATCH_LOOSE', 1 << 1);
define('FILTER_INVERT', 1 << 2);

function filter(mixed $specimen, int $flags = FILTER_MATCH_EXACT): Closure
{
    // Unset FILTER_MATCH_EXACT if FILTER_MATCH_LOOSE is set.
    if ($flags & FILTER_MATCH_LOOSE) {
        $flags &= ~FILTER_MATCH_EXACT;
    }

    // int, float, string or bool
    if (is_scalar($specimen)) {
        $function = <<<'PHP'
return static function (mixed $test) {
    return $test ###COMPARISON### ###SPECIMEN###;
};
PHP;
        $comparisonPrefix = ($flags & FILTER_INVERT) ? '!' : '=';
        $comparison = ($flags & FILTER_MATCH_EXACT) ? $comparisonPrefix . '==' : $comparisonPrefix . '=';

        $functionFactory = str_replace(
            ['###COMPARISON###', '###SPECIMEN###'],
            [$comparison, var_export($specimen, true)],
            $function
        );
        return eval($functionFactory);
    }
    // Not implemented
}