diagnostics will tell you which category a warning belongs to: 
Possible attempt to put comments in qw() list at
        /temp/pm line 21 (#1)
    (W qw) qw() lists contain items separated by whitespace; as with l
+iteral
...

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The last line quoted above starts (W qw) telling you that this warning belongs to the qw category.

In reply to Re^2: Hex to array conversion by FunkyMonk
in thread Hex to array conversion by Anonymous Monk

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