Almost ... try this instead: 
while (<USEDPW>) {
   my $pw = @chars[map{rand @chars} (1..17)];
}
unless ($_ ne $usedpw) {
   print "Your unique ID is: $pw\n";
}

[download]
or this: 
while (<USEDPW>)
{
   my $pw = @chars[map{rand @chars} (1..17)];
}
unless ($_ ne $usedpw)
{
   print "Your unique ID is: $pw\n";
}

[download]
Whether you like to hug the open brace (example 1) or put it's on it's own line (example 2) is a matter of personal preference - both are correct. However, you really need to line the closing brace up with what started it. Also, i recommend using tabs instead of spaces - you can always use a tool like expand to convert each tab to any number of spaces. For comments to the left of code, well, i try to avoid them, but when i have to have to have them i use spaces to line them up. Keep up the good work. :)

Oh yeah ... you can simplify the unless block like so: 

print "Your unique ID is: $pw\n" if $_ eq $usedpw;

[download]
... and double negatives are bad habits, notice that i replaced unless with if and ne with eq.

jeffa

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)

In reply to (jeffa) 2Re: Losing or overwritting values by jeffa
in thread Losing or overwritting values by sulfericacid

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