Re: [E] Regexp_replace bug / does not terminate on long strings

> On Aug 20, 2021, at 12:51 PM, Miles Elam <miles.elam@productops.com> wrote:
>
> Unbounded ranges seem like a problem.

Seems so.  The problem appears to be in regcomp.c's repeat() function which handles {1,SOME} differently than {1,INF}

> Seems worth trying a range from 1 to N where you play around with N to find your optimum performance/functionality
tradeoff.{1,20} is like '+' but clamps at 20. 

For any such value (5, 20, whatever) there can always be a string with more repeated words than the number you've
chosen,and the call to regexp_replace won't do what you want.  There is also an upper bound at work, because values
above255 will draw a regex compilation error.  So it seems worth a bit of work to determine why the regex engine has
badperformance in these cases. 

It sounds like the OP will be working around this problem by refactoring to call regexp_replace multiple times until
allrepeats are eradicated, but I don't think such workarounds should be necessary. 

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Mark Dilger
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