I realize you already have a solution, but what about this: 
sub boldify
{
    local $/ = undef;
    my $input = shift;
    my @parts = split /``/, $input;
    foreach my $i (0..scalar(@parts)) {
    $parts[$i] =~ s/\*\*(.+?)\*\*/<b>$1<\\b>/gs if ($i % 2 == 0);
    }
    return join '', @parts;
}

[download]

Here's a test: 

my $test_data = <<INPUT;
This is **bold**, but ``this is **not** bold``
``This is **not** bold``, but this is **bold**, and ``this is **not** 
+bold``
This sure is **bold** and so is **this**, but ``**this**`` aint
INPUT

print boldify($test_data);

[download]

output 

This is <b>bold<\b>, but this is **not** bold
This is **not** bold, but this is <b>bold<\b>, and this is **not** bol
+d
This sure is <b>bold<\b> and so is <b>this<\b>, but **this** aint

[download]

In reply to Re: Interpolate Text Not Inside a Certain Tag by satchm0h
in thread Interpolate Text Not Inside a Certain Tag by Anonymous Monk

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