Yes and no.

It's not possible to get a reliable answer for scalar package variables, but you can get a close enough answer. (If pkg var @foo exists, so does $foo even if it's never used.)

It's not possible with lexical variables unless you're ok with actually executing the literal (and thus arbitrary code) to find out.

There are template systems that use the syntax of Perl's interpolating literals.

In reply to Re^3: Using a sting with a variable name by ikegami
in thread Using a sting with a variable name by bingohighway

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