Since arguments are passed _by alias_, doing things to $_[0] actually changes the first argument (and so on). E.g.: 
sub frobnicate {
  $_[0] =~ s/foo/bar/;
  $_[0] =~ s/\d/\&/g;
}

my $var = "foo 12345";
frobnicate($var);
# $var is now "bar &&&&&"

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Of course, there is no "One True Way," but this is clean and works.

In reply to Re: style q: duplication? of variables by nakor
in thread style q: duplication? of variables by thpfft

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