You could poison them with a tie to catch uses at runtime:

package Tie::Poison;
sub TIESCALAR {
...
}

sub TIEARRAY {
...
}

sub FETCH {
    my $var = tied $_[0];
    die "Prohibited variable '$$var' used";
}

package unusual_variable_names;
our @unusual = qw(
    @@
    @$
    ...    
);

sub unimport {
    for my $name (@unusual) {
        no strict 'refs';
        tie @{ $name }, 'Tie::Poison', $name;
    };
};

...

package main;
no unusual_variable_names;

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In reply to Re^3: Code Loop? by Corion
in thread Code Loop? by bitman

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