well, in your complete code you have  do ( local $/: <MAT> ) while I wrote  do { local $/; <MAT> } can you spot the two subtle differences ;-)

There are curly braces not parentheses and there is a semicolon not a colon between the two expressions.

You say that your code crashes on you. It would be good if you supplied the error message you are getting. Crashing sounds so much like a core dump - which is never supposed to happen.

Hth

-- Hofmator