That's not trivial. Defining a constant using the constant pragma means a subroutine with that name is created - a subroutine without a prototype.

Now, it's fairly easy to test if there's a subroutine defined given a name, and it's also fairly easy to see whether it has an empty prototype. But not every function with an empty prototype is a constant.

So, you may have to resort to introspection tools like Devel::Peek. It's Dump function can tell whether a subroutine is a constant - look for the CONST flag. Dump writes to STDERR, so if you want to do this from within your program, you may want to redirect STDERR and capture it yourself.

In reply to Re: Constant name stored in a string by JavaFan
in thread Constant name stored in a string by SBECK

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