in reply to Re: Perl Syntax that we generally don't know or forget.
in thread Perl Syntax/resources that we generally don't know or forget.

No! Don't stop there! You can also use the lvalue bindings of argument passing! Three nested lvalue usages: 
my $value = "abcde";
sub attack { $_[0] = "x" }
attack($_) for substr($value, 2, 1);
print "$value\n"; # prints "abxde\n"

[download]
And if I understood lvalue subroutines better, I could probably write "attack($_) = 'x'" instead, for a fourth layer. {grin}

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

Replies are listed 'Best First'.
Re: •Re: Re: Perl Syntax that we generally don't know or forget.
by shotgunefx (Parson) on Jan 18, 2004 at 18:15 UTC
    Like this?. Or is there something I'm missing here.. 
    sub  attack :lvalue {
  substr($_[0], 2, 1) ;
}

    [download]

    -Lee

    "To be civilized is to deny one's nature."
[reply]
[d/l]
      That is supposed to work, but currently has some problems (see perl bug #24200) if you call attack in an rvalue context after calling it in an lvalue context.
[reply]

In Section Cool Uses for Perl