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On 14 March 2011 08:14, Benoit Germain <> wrote:
>> -----Original Message-----
>> From: []
>> On Behalf Of Roberto Ierusalimschy
>> Sent: Thursday, March 10, 2011 3:00 PM
>> To: Lua mailing list
>> Subject: Re: How to extract a word at a given position in a string?
>> What is wrong with reversing the string ('string.reverse')?
>> -- Roberto
> [BG] Reversing the string is fine when it is rather small (which is my case).
> However, I suppose one can encounter a situation where a large text has to be searched,
> and there is no easy means of extracting a small portion to search in. In that case,
> duplicating the whole text, and searching through it, is expensive.
> I was just wondering if there was a possibility to apply all pattern matching functions
> in the reverse direction.

GNU regex allows this, and lrexlib 2.5.x supports backwards searching
when using it. GNU regex supports POSIX syntaxes.