"use constant" creates a parameter-less subroutine to define the constant. Unfortunately, the quoting of a hash key bareword and the bareword quoting to the left of a fat arrow are stronger than the execution of subroutine to get its value.

A simple workaround is to add an extra set of parens: 

my %hash = (
  (FOO) => 35,
  (BAR) => 19,
);
print $hash{(FOO)};

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There are other ways around, but I think this is the cleanest.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: explanation of constant syntax? by merlyn
in thread explanation of constant syntax? by Anonymous Monk

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