You have inadequately said what you are looking for in your answer. The following will match all the above possible combinations in $result, but I strongly suspect that it is not what you want 
my $result = $string;

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If you spot any bugs in my solutions, it's because I've deliberately left them in as an exercise for the reader! :-)

In reply to Re: regex help required by space_monk
in thread regex help required by ghosh123

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