PHP: Match Each Array Item Once With All The Other Array Items

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OBJECTIVE: given an array, return all the combinations of each item once with each other, without duplicates.  

function arrayCombinator(&$array){
if(!is_array($array)){return $array;/*or php sizeof() matches Strings too!*/};
$output=array(); $L=sizeof($array); $i1=-1;
while(++$i1<$L){
$compare=array_shift($array);
	$L2=sizeof($array)-$i1; $i2=-1;
		while(++$i2<$L2){/*kernel is here:*/ $output[]=array($compare, $array[$i2]); }
array_push($array, $compare);
}
return $output;
/*keep comment to use freely:
http://www.fullposter.com/?1*/}

Remove colors  
INPUTS: an array.  
 
RETURNS: an array.  
 
CAVEATS: the input array is affected, but eventually returned unaltered unless you perform operations within the kernel that manipulate and alter the data. To avoid this, remove the pointer from the function signature namely the & sign before the input argument.  
 
Within the section dubbed "kernel" (in a comment), you may add custom code, namely remove entirely all the $output variable related parts, and manipulate directly the

$compare
$array[$i2]

Remove colors items with code of your own: in fact, those items are your combinations in progress.  
 
You may even consider producing maps: if you have to manipulate repeatedly some input array of, say, 30 entries, produce first an output with an array in the range(0,29) (whereas 29 is 30-1) and pass it to this function; then, to grab the combinations from the input array you may just use the indexes of the firstly produced array as a map (arguably to serialize for later use): so you run the function only once - in a lifetime, at least for all arrays whose length is either equal or inferior to 30.  
 
Example:

$afoo=array(0,1,2,3,4,5,6);
print_r( arrayCombinator($afoo) );

Remove colors

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