The g means to search the whole string and the i searches case-insensitively (so that FrEd still matches). The \U just uppercases everything (in this case $1). As for the $1 and join, data64 pretty much has it covered.

Update: zengargoyle has also done a good (and probably better) job of explaining it piece by piece.

In reply to Re: Learning Perl 3 questions (misc) by The Mad Hatter
in thread Learning Perl 3 questions (misc) by sulfericacid

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