With constants, I can test that one is defined, or use it trivially: 

   use constant FOO => 42;
   print defined(FOO);
   print FOO;
Now, if I have the name of the constant stored in a string: 
   $var = "FOO";
how can I operate on $var to find out if the constant stored in it's name is defined, and what it's value is?

If I'm understanding what I've read, it may not be possible... but if it is, I'd like to know how.

Thanks

In reply to Constant name stored in a string by SBECK

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