Actually tracking down diagnostic messages is one thing where people Really Should use the online documentation. They change a lot from release to release, and not knowing how to get the ones for your version of Perl can seriously confuse. (There was a thread once involving our where that came up, there was nothing in 5.003 and hence Camel 2, it exits in 5.6 and hence Camel 3, but in 5.005 the word was reserved and generated a warning that confused some...)

In this case you first type: 

perldoc perldiag

[download]
then type: 
/Useless use

[download]
then type "n" until you get to the right message. If you go too far type "1G"

Where I said "Useless use" above I just wanted some part of the fixed error message. Usually it isn't hard to guess, but sometimes you will need to try twice to figure out what it should be.

That will give you messages that are appropriate for your version of Perl.

In reply to Re (tilly) 2: useless use of a constant in a void context? by tilly
in thread useless use of a constant in a void context? by princepawn

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