it is not an error message

He made an error (concatenated two variable without giving either a value) and Perl issued a message in response to that error. How is that message not an error message? It's simply not an (immediately) fatal error.

is probably because you have empty lines in your __DATA__ area.

No, he gets the warning before even executing <DATA> because he's using a bottom tested loop.

In reply to Re^2: How to use __DATA__ efficiently, help! by ikegami
in thread How to use __DATA__ efficiently, help! by Anonymous Monk

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