From perldoc perlsyn it says that the LABEL goes with a block, and is just like creating a single-iteration loop. So if you think of the COPY: and 'stupid' line as $J="blah" for 1; you can see why COPY: immediately followed by the use statement wouldn't work. You can solve this by using curly brackets, but a better solution would be to pull the use File::Copy; statement towards the top of your file. It is run at compile-time anyways, so having it in the block (which may or may not be run) doesn't gain you anything.