I tend to agree on the relatively low frequency that people might make this kind of mistake. But:

Also, "Probably" doesn't really belong in warnings :) it means this shouldn't be a warning

I beg to differ. Perl has quite a few warnings of this very nature, where a syntax is perfectly valid but probably not what the programmer meant. Some examples (see perldiag for more details and a more complete list): 

       Possible attempt to put comments in qw() list
       Possible attempt to separate words with commas
       Possible memory corruption: %s overflowed 3rd argument
       Possible precedence issue with control flow operator
       Possible precedence problem on bitwise %s operator
       Possible unintended interpolation of $\ in regex
       /%s/ should probably be written as "%s"

In reply to Re^2: "Useless use of a constant" in grep block? by perlancar
in thread "Useless use of a constant" in grep block? by perlancar

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