And just to add to Roger's comment ... ;)

I never use a hash slice unless i know that the array containing the keys has no duplicates. Now, i know that sometimes this just isn't practical, but i really only use hash slices when i know what the keys are going to be -- that is, i don't use them when i don't know what the keys are going to be. Besides, 99% of the time, you see the creating of a hash slice like so: 

my %month;
my @month = qw(Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec);

@month{0..$#month} = @month;

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... that is, you declare the keys and the values. As long as this is true, you shouldn't have to worry about writing code to catch duplicates. On the other hand, something like: 
print "Enter keys (sep with space): ";
chomp (my $key = <STDIN>);

print "Enter vals (sep with space): ";
chomp (my $val = <STDIN>);

my %hash;
@hash{ split '\s',$key } = split '\s',$val;

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is just asking for trouble. I would instead (sigh) explicitly code out a "standard" for loop to ensure that duplicates were caught, as well as a mismatching number of keys and vals.

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 3Re: Two arrays. One hash. by jeffa
in thread Two arrays. One hash. by matt me

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