Do you not get the following kind of warning when you use the fat comma in your code?

Useless use of private variable in void context at...

I get the warning when I run this code (v5.8.0 built for x86_64-linux-thread-multi):

#!/usr/bin/env perl

use warnings;
use strict;

my $count = 9;
my $i = 0;
while ($i<5) {
    next unless $count => 8;
    $i++;
}
print "end\n";
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The "=>" operator is described in perlop as:

The => operator is a synonym for the comma, but forces any word (consisting entirely of word characters) to its left to be interpreted as a string (as of 5.001). This includes words that might otherwise be considered a constant or function call.