Yup, it's really just that simple (well, maybe exists rather than defined; but that's a minor nit). If your files are really, really big you probably want to use something like Berkeley_DB or one of the other DBM modules rather than reading everything into memory, but that's just an implementation detail; the basic algorithm remains the same.

In reply to Re^2: comparing two files for duplicate entries by Fletch
in thread comparing two files for duplicate entries by Angharad

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