I'm embarassed to admit how long I've been writing Perl, and had never caught on to this little pitfall: 
  my $a = 1 and 0;

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Since the and operator has lower precedence than =, this sets $a to "1". Apparently no warning is issued, either.

In my defense, the actual code in which this came to light was a bit more complex: 

    my $can_remote =
      defined($cfg->remote) and
      (($cfg->get('remote') eq 'all') or
      grep($type eq $_, split(/\s+|,\s*/,$cfg->get('remote'))));

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Of course, changing and to && solves the problem. However, now I'm faced with a big problem: How do I scan 100,000 lines of Perl in our application code base to look for other places where I've done this?!?
--
Jeff Boes
Database Engineer
Nexcerpt, Inc.
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In reply to Operator precedence (or, I'm an idiot) by Mur

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