Maybe this is satisfactory? 
#!/usr/bin/perl -l

use strict;
use warnings FATAL => 'syntax';
use List::Util qw/reduce/;

print reduce( sub {
    $a * $b;
}, 1..6);

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In reply to Re: Name "main::a" used only once: possible typo by Khen1950fx
in thread Name "main::a" used only once: possible typo by szabgab

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