Java > Scala

[Jonathan M Davis]

On Saturday, December 03, 2011 01:44:33 Dmitry Olshansky wrote:
> On 03.12.2011 1:08, Marco Leise wrote:
> > Cool, thx for your answers. The source code for OpenJDK can be
> > downloaded if you want to take a look at it. You are probably right
> > about them not decoding the characters lazily since their strings are
> > UTF-16.
> > The commented version of opIndex is a bit faster on my Core 2. This is
> > the first time that I witnessed such speed differences between
> > processors. :)
> 
> Wow. I knew something was wrong with non-BT test code, from what I heard
> it should have been faster but it wasn't for me :)
> 
> > Also I found that the trie is usually queried twice for each matching
> > character in the input string. You can't optimize opIndex any further
> > (but try size_t in there instead of uint, it helped here) unless you
> > make some changes on the larger scale. So if you should find out that
> > the second query isn't required, that would help more than anything
> > else.
> > I said it on IRC today: This library will be my reference for compile
> > time code generation in D. There is a lot of expertise in it, good work!
> 
> There I have two options to work through:
> - separate negative and positive character classes it would kill
> possible branching here.
> - and now looking at test_11 in you profile output, I see the likely
> culprit: I should re-think lookahead tests, they used to reduce number
> of savepoints during matching.
> 
> > P.S.: I'm fine with treating anything that is escaped, but not special,
> > as is. \w did cause an infinite loop though, so you may want to test
> 
> Hm can't reproduce.
> 
> > with the original regex. For \. you can assert(false, "\. is not a valid
> > escape sequence")
> 
> No that was bad idea ... and I planed to change that exception. Now I'm
> more into ignore the backslash.
> 
> or just ignore the backslash. Personally I usually
> 
> > don't escape anything just to be on the safe side. :p
> 
> Worthy of a small community poll.

Also, in case you didn't see it:

http://d.puremagic.com/issues/show_bug.cgi?id=7045

- Jonathan M Davis