Besides the parens (around or following) and the ampersand, you can use an unary plus - the Perl way of disambiguating whether you are referring to an expression or something else. 
my %capitol_map = (
    +WISCONSIN => "Madison",
    +ILLINOIS  => "Springfield",
    ...
);

[download]
 See rir's post below..

Makeshifts last the longest.

In reply to Re: use constant for strings (unary plus) by Aristotle
in thread use constant for strings by shemp

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