but I can't figure out why this doesn't work. Doesn't shift work on @_ by default?

Yes and no: see shift. This is an example of Do What I Mean (DWIM). Inside a subroutine or format, shift works on @_ by default. Outside a subroutine, however, shift works on @ARGV by default. 

#!perl -l

@ARGV = '@ARGV';
@_ = '@_';

print '$ARGV[0] = ', shift;

mysub(@_);

sub mysub {
  print '$_[0] = ', shift;
}

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In reply to Re: Re: for vs. reverse by chipmunk
in thread for vs. reverse by Corion

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