Re: [PATCH] regexp_positions ( string text, pattern text, flags text ) → setof int4range[]

[Mark Dilger]

> On Mar 2, 2021, at 5:34 AM, Isaac Morland <isaac.morl...@gmail.com> wrote:
> 
> Returning to the RE result issue, I wonder how much it actually matters where 
> any empty matches are. Certainly the actual contents of the match don’t 
> matter; you don’t need to be able to index into the string to extract the 
> substring. The only scenario I can see where it could matter is if the RE is 
> using lookahead or look back to find occurrences before or after something 
> else. If we stipulate that the result array will be in order, then you still 
> don’t have the exact location of empty matches but you do at least have where 
> they are relative to non-empty matches.

I agree the contents of the match don't matter, because they are always empty.  
But the position matters.  You could intend to split a string in multiple 
places using lookaheads and lookbehinds to determine the split points.

—
Mark Dilger
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