I am having some trouble with using a constant string. Specifically i have code along the following line: 
use constant WISCONSIN => "WI";
use constant ILLINOIS => "IL";
...

my %capitol_map = (
    WISCONSIN => "Madison",
    ILLINOIS  => "Springfield",
    ...
);

...
my $abbrev = "WI";

if ( exists $capitol_map{$abbrev} ) {
    print "capitol = $capitol_map{$abbrev}\n";
}

[download]
exists() returns false.
I had assumed that in the hash creation, that the constants would be interpolated into their text values. This is not the case though, and if i look at the hash with Data::Dumper, the keys look like WISCONSIN or ILLINOIS
I must be missing some subtle point here.
thanks

In reply to use constant for strings by shemp

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