I don't see that as separate statements

Perl::Critic doesn't understand 100.00% of Perl. But then again, if perlcritic is misreading that statement, other people might too. perlcritic doesn't complain with both {$_=>0} or {($_,0)}, and those make it a little more obvious what you're trying to do.

Anyway, to get an explanation from perlcritic, add the option --verbose 11:

$ perlcritic -3 --verbose 11 1129720.pl 
Comma used to separate statements at line 7, near '$_,0'.
ValuesAndExpressions::ProhibitCommaSeparatedStatements (Severity: 4)
Perl's comma statement separator has really low precedence, which
leads to code that looks like it's using the comma list element
separator not actually doing so. Conway suggests that the statement
separator not be used in order to prevent this situation.
...

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In reply to Re: explain perlcritic by Anonymous Monk
in thread explain perlcritic by EBADF

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