I would suggest that using the lexical variable for the filehandle is a good idea even in small one-off scripts. A very wise person once told me

There is nothing more permanent than temporary code.

Quite often quick-and-dirty scripts grow and become critical. Also, using the lexical filehandles is a good habit to cultivate.

On the other hand, I often prefer to use $_ rather than an explicit variable in small loops. For me that's more of a style issue than anything else.

Exactly. If you are feeling (over)confident you can just code this:

open (FILE, $filename) or die $!;

print while <FILE>;
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Or on the command line:

perl -pe '$_' file.txt
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UPDATE: thanks for the correction, quester

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Pardon me, but even one liners need to enable warnings...

$ perl -wpe '$_' file.txt
Useless use of a variable in void context at -e line 1.
...
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It should actually just be

$ perl -wpe '' file.txt
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