Multiple occurrences in $array1 are all treated the same way.
This will output :
Array
(
[1] => blue
)
Note:
Two elements are considered equal if and only if
(string) $elem1 === (string) $elem2. In words:
when the string representation is the same.
Note:
Please note that this function only checks one dimension of a n-dimensional
array. Of course you can check deeper dimensions by using
array_diff($array1[0], $array2[0]);.
