Unless you're sure that the input file will only contain safe characters, you should call quotemeta on $_ inside the map.
Also, what's the benefit of chaining two map's like that, instead of combining them into one?

Edit: Oops, I only just now noticed that choroba already mentioned quotemeta in his answer. Sorry for the redundancy.

In reply to Re^2: Best approach to creating a regex from a filehandle by smls
in thread Best approach to creating a regex from a filehandle by fieroboom

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