if (thatroutine()) {return $_}

$_ isn't getting set there. Are you expecting the variable to be psychic?

No, I'm not expecting that. I tested this with a one-liner prior to posting, I swear. Problem is, I just tried re-entering that one-liner prior to posting my proof here and.... It doesn't work. I suppose I must have screwed that up somehow, the first time around. I'm not entirely clear on how $_ works.

$_ is set by very few things:
• An explicit assignment ($_ = 35).
• The implicit setting for a while() loop reading from a filehandle:

  while (<HANDLE>) { ... } # same as ...
  while (defined($_ = <HANDLE>)) { ... }
  [download]

• The implicit variable of a foreach loop:

  foreach (@list) { ... } # same as foreach $_ (@list) { ... }
  [download]

• The implicit variable of a grep/map block (added after prodding, sorry):

  $count = grep { BLOCK } LIST;
  @result = grep { BLOCK } LIST;
  @result = map { BLOCK } LIST;
  map { BLOCK } LIST; # invalidates your warranty
  [download]

I think that's it. I don't recall anything else that can set the value. Lots of operations can alter the value, like chomp or s///.

-- Randal L. Schwartz, Perl hacker
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