The following is just not working. Basically, i want to match a value that has "equity",but NOT "private equity". The result must be items 1, 2, 4, 5. Please check this out: 
my %hash = (
    1        => 'equity, private equity',
    2        => 'equity',
    3        => 'private equity',
    4        => 'private equity,equity',
    5        => 'private equity, equity',
    6        => 'equity,private equity',
    7        => 'private equity',
    8        => 'mutual funds',
    9        => 'cds'
);

while (my ($k, $v) = each %hash) {
    next unless $v =~ m/(?!private\s+)equity/;
    printf("%d -> %s\n", $k, $v);
}

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In reply to Re: Using Look-ahead and Look-behind by Anonymous Monk
in thread Using Look-ahead and Look-behind by Roy Johnson

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