C++ Weekly - Ep 74 - std::regex optimize

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Source:

[stevenelliott]

I got a 25% speed-up by setting the youtube speed to 1.25

[SnakeBackwards]

Got a nearly 5X speed up by making it static and another 2X by optimizing for a total 10X speed up. This was EXTREMELY helpful and informative. I had no clue construction was the real culprit and was worried we'd have to do some magic with the actual regex string itself and was worried it'd be super complicated.

[SonicFan]

If you want to keep the scope limited I suppose you could just swap the while-loop out for a for-loop like this:
for( const std::regex regex(...); state.KeepRunning(); )

[danielphd]

Hello Jason, glad to see this new video. Can you do another video to detail how capturing a substring of a string relatively to a pattern ? What is the functionnality needed ? Thanks

[Galaf]

I don't understand. the std::regex optimize didn't do anything, the fact to move a variable declaration did the trick. It has nothing to do with the flag?

[yehezkelshb]

I'd expect compiler optimization to take the init outside of the loop. Maybe using a higher optimization level is what was needed?

[mipmap]

Did I missed anything.
Put the std::cmatch in while loop will be slow of course, becuase it's construct many many times. This is nothing related to limit cmatch scope.
I really like Jason's video. I learned a lot from all these videoes. I'm not trying to pretend to be smart. I just got confused.

[kipu]

So the optimize flag doesn't make any significant difference? What about benchmarking it the with O3 optimization?

[konrad]

Why some people strange pronounce "STD" as "stood"? Is it correct?