Hidden features of Perl?

Answer 1

Add support for compressed files via magic ARGV:

s{ 
    ^            # make sure to get whole filename
    ( 
      [^'] +     # at least one non-quote
      \.         # extension dot
      (?:        # now either suffix
          gz
        | Z 
       )
    )
    \z           # through the end
}{gzcat '$1' |}xs for @ARGV;

(quotes around $_ necessary to handle filenames with shell metacharacters in)

Now the <> feature will decompress any @ARGV files that end with ".gz" or ".Z":

while (<>) {
    print;
}