Single Comment

Okay, I fixed the push command. The problem was that an empty array was being interpreted as a null value, and isset returns false when a variable has a null value. This problem has not shown up with zero values, because PHP does not treat zero as a null value, and isset will normally recognize a variable set to zero as set. The fix combines isset with array_key_exists, using isset to check whether any variables for the scope exist and array_key_exists to check for the named variable. I need to use isset before array_key_exists to avoid error messages from array_key_exists when the array it is supposed to search for a variable doesn't exist.