That example does not produce an error. 
$ cat psychotic.pl 
my @found;
my $line = 'Alpha and some junk here';
my @keywords = qw(alpha beta gamma);

foreach (@keywords) {
    $line =~ m/$_/i ? push @found, $_ : next
}

foreach (@found) { print }

$ perl psychotic.pl  ; echo
alpha

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In reply to Re^2: Missing $ on loop variable by superfrink
in thread Missing $ on loop variable by superfrink

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