Recently one of my friends wrote a guess-the-word game in c, which prompted me to write a shorter one in perl, with more features. The coding was fine until I decided to support an option to use a random word from /usr/dict/words as the answer as opposed to one entered to <>.

Essentially the problem was that I passed the dict as $ARGV[0] and subsequently attempted to use <>, only to find that the behavior changed due to the presence of @ARGV as per perlop <EXPR>. While I was able to "fix" the code by clobbering @ARGV, equating it to the empty list, this brings me to the crux of my question:

When using both @ARGV and <STDIN>, what's the perlish implementation without clobbering @ARGV?

I would presume explicit use of <STDIN> or even readline(*STDIN) is better coding practice, but I'm at a loss as to a perlish impelementation.

UPDATE: By request, the guess-the-word game code:

#!/usr/bin/perl -w

use strict;

my ($answer, $guess, $guesses) = ("", "", 0);
if (@ARGV) {
        open FILE, $ARGV[0] or die "No such dictionary...";
        rand($.) < 1 && ($answer = (split(/[\r\n]+/,$_))[0]) while <FI
+LE>;
        close FILE;
        @ARGV = ();
} else {
        $answer = (split(/[\r\n]+/,<>))[0];
}
system 'clear';

do {
        $guess = (split(/[\r\n]+/,<>))[0];
        unless ($guess eq $answer) {
                if (length $guess != length $answer) {
                        print "The answer is ", length $guess > length
+ $answer ? "shorter" : "longer", "\n";
                } else {
                        print "The $$_[0] letter ($$_[1]) is ", $$_[2]
+? "" : "in", "correct\n" foreach map { [$_, (split //, $guess)[$_], (
+split //, $guess)[$_] eq (split //, $answer)[$_] ? 1 : 0 ] } (0..(len
+gth $guess) - 1);
                }
        } $guesses++;
} while ($answer ne $guess);

print "You figured it out in a mere $guesses guesses\n";
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Lastly, I should note that this was a question of style and practice, rather than a request for help with a particular code. After reading the reply by EvanCarroll, which concurs with my presumption that using <STDIN> is better programming practice, I re-read perlop and discovered several loops of the form:

while (<>) {
...
}
[download]

When I read such passages while learning perl, I misunderstood <> for <STDIN>. While this misunderstanding has taken awhile to surface, I now know the distinction between <> and <STDIN>.

Thanks to everyone who helped out -- and feel free to try the game :-)