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run code in 300+ PHP versions simultaneously

@ 2014-10-30T08:00:42Z

<?php

/*
span                    :: (a -> Bool) -> [a] -> ([a],[a])
span _ xs@[]            =  (xs, xs)
span p xs@(x:xs')
         | p x          =  let (ys,zs) = span p xs' in (x:ys,zs)
         | otherwise    =  ([],xs)
*/
function span($p, $xs) {
    if (empty($xs)) {
        return [[], []];
    }

    $xs_ = $xs;
    $x = array_shift($xs_);

    if ($p($x)) {
        list($ys, $zs) = span($p, $xs_);

        return [array_merge([$x], $ys), $zs];
    }

    return [[], $xs];
}

/*
groupBy                 :: (a -> a -> Bool) -> [a] -> [[a]]
groupBy _  []           =  []
groupBy eq (x:xs)       =  (x:ys) : groupBy eq zs
                           where (ys,zs) = span (eq x) xs
*/
function array_group(callable $eq, array $xs) {
    if (empty($xs)) {
        return [];
    }

    $x = array_shift($xs);
    // curry of $eq
    $eqx = function ($y) use ($eq, $x) { return $eq($x, $y); };

    list($ys, $zs) = span($eqx, $xs);

    return array_merge([array_merge([$x], $ys)], array_group($eq, $zs));
}

function it($m,$p){echo ($p?'OK':'NO')." It $m\n"; if(!$p){$GLOBALS['f']=1;}}
function done(){if(@$GLOBALS['f'])die(1);}

it('spans elements which match', span(function ($x) { return $x < 3; }, [1, 2, 3]) === [[1, 2], [3]]);
it('spans elements which match from the start', span(function ($x) { return $x == 3; }, [1, 6, 3, 3]) === [[], [1, 2, 3, 3]]);
it('spans returns empty lists on empty list', span(function ($x) { return false; }, []) === [[], []]);


it('groups elements recursively', array_group(function ($a, $b) { return $a <= ($b-1); }, [1, 1, 2, 1]) === [[1, 1], [2], [1]]);

Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6: OK It spans elements which match NO It spans elements which match from the start OK It spans returns empty lists on empty list NO It groups elements recursively
Output for 8.3.5: Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 OK It spans elements which match NO It spans elements which match from the start OK It spans returns empty lists on empty list NO It groups elements recursively
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29: Parse error: syntax error, unexpected '[' in /in/R58qO on line 12
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5: Parse error: parse error, unexpected '[' in /in/R58qO on line 12
Process exited with code 255.
Output for 4.3.2 - 4.3.4: Parse error: parse error in /in/R58qO on line 12
Process exited with code 255.

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