Jelle-S/arraykeycombiner

# ArrayKeyCombiner
 
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Combines arrays by searching for intersections and adding them to the master array. Keys are combined using a delimiter.
 
```php
use Jelle_S\Util\Combiner\ArrayKeyCombiner;
 
// Search this array of arrays for intersections and extract them, using a
// delimiter to combine the keys. Limit the number of iterations to search for
// intersections to 10.000, limit the minimum size of intersections to 3, set
// the key delimiter to a comma.
$arrays = array(
 array(
   'a' => 1,
   'b' => 2,
   'c' => 3,
   'd' => 4,
   'e' => 9,
 ),
 array(
   'a' => 1,
   'b' => 2,
   'c' => 3,
   'e' => 9,
 ),
 array(
   'a' => 1,
   'b' => 42,
   'c' => 3,
   'd' => 4,
 
 ),
 array(
   'b' => 42,
   'c' => 3,
   'a' => 1,
 ),
 array(
   'z' => 26,
   'e' => 9,
   'a' => 1,
 ),
);
$combiner = new Jelle_S\Util\Combiner\ArrayKeyCombiner($arrays, 3, 10000, ',');
print_r($combiner->combine());
```
 
Output:
```
Array
(
    [4] => Array
        (
            [a] => 1
            [e] => 9
            [z] => 26
        )
 
    [0,1] => Array
        (
            [a] => 1
            [b] => 2
            [c] => 3
            [e] => 9
        )
 
    [2,3] => Array
        (
            [a] => 1
            [c] => 3
            [b] => 42
        )
 
    [2,0] => Array
        (
            [d] => 4
        )
 
)
```
 
The 'a' and 'z' keys of the array with key '4' were not combined because the threshold for combinations is 3, and combining them would result in a combined array with only two elements.
 
The arrays with keys '2' and '0' **were** combined because after extracting the combinations, these two arrays were identical, and the threshold has no effect for **identical** arrays, they are always combined.