in reply to for vs. reverse

This works, maybe this is not as good as the others. 
@_ = (@{$_ = [qw{emacs vi}]}, reverse @$_);
print "Why do we have to hide from the police, daddy ? Because they us
+e ", shift @_, " and we use ", shift @_, ", son.\n" while(@_);

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but I can't figure out why this doesn't work. Doesn't shift work on @_ by default? 
@_ = (@{$_ = [qw{emacs vi}]}, reverse @$_);
print "Why do we have to hide from the police, daddy ? Because they us
+e ", shift, " and we use ", shift, ", son.\n" while(@_);

[download]

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Re: Re: for vs. reverse
by chipmunk (Parson) on Mar 28, 2001 at 09:33 UTC
    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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[d/l]

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