• while (<>) { ... } or while (my $line = <>) { ... }?

  Almost always the former. Occasionally the latter, if using $_ won't make the loop body any simpler and I'm not dealing with lines as text strings (for instance, while (my $addr = <>) for a file full of IP addresses), but that's a rare thing.

• -w or use warnings;?

  -w. Most of my scripts target 5.005_03.

• sub CONSTANT () { ... } or use constant CONSTANT => ...;?

  I don't usually enforce constness. I'm much more likely to say $main::CONSTANT = 'foo'; and just not touch any identifiers in all caps.

• my ($foo, $bar) = @_; or my $foo = shift; my $bar = shift;?

  Always assign from @_. Less verbose, easier to change, and the list looks more like a formal parameter list to my C-trained eyes.

• for (@array) { ... } or foreach (@array) { ... }?

  for. It's less than half the length of foreach. Huffman encoding, etc, etc.

• print 'foo'; or print('foo');?

  Without brackets, unless that induces precedence lossage.

• 'simple string' or "simple string"?

  I'm trying to avoid double-quoted strings unless there's actually some interpolation going on, but I've already formed the habit of double-quoting all strings. We'll see which one wins.

• glob '*' or <*>?

  Explicit glob. Angle brackets read from filehandles.

• readline *FOO or <FOO>?

  <FOO>. Again, angle brackets read from filehandles.

• for (keys %foo) { $_ and $foo{$_} } or while (my ($key, $value) = each %foo) { $key and $value }?

  Usually for (keys %foo), but more out of habit than anything else.

In general, I try for the tersest code that doesn't require a comment.

--
F o x t r o t U n i f o r m
Found a typo in this node? /msg me
The hell with paco, vote for Erudil!