in reply to (code) Re: (2) More efficient munging... (improved lc() uc() snippet)
in thread More efficient munging if infile very large

see perlman:perlop and look for the section on Conditional Operator. It's basically an in-place if-then type of construct that evaluates the EXPR $uclc eq 'lc' and returns lc() if the EXPR is true or uc() if the EXPR is false.