Also add exp/regexp to build (forgot before).
At this point I am very confident in exp/regexp's
behavior. It should be usable as a drop-in
replacement for regexp now.
Later CLs could introduce a CompilePOSIX
to get at traditional POSIX ``extended regular expressions''
as in egrep and also an re.MatchLongest method to
change the matching mode to leftmost longest
instead of leftmost first. On the other hand, I expect
very few people to use either.
R=r, r, gustavo
CC=golang-dev
https://golang.org/cl/4990041
Still need to write tests for new syntax
and fix bugs that the tests find, but this
is a good check point.
All tests pass.
Compared against existing regexp:
benchmark old ns/op new ns/op delta
regexp.BenchmarkLiteral 1869 620 -66.83%
regexp.BenchmarkNotLiteral 9489 7823 -17.56%
regexp.BenchmarkMatchClass 10372 8386 -19.15%
regexp.BenchmarkMatchClass_InRange 10800 7750 -28.24%
regexp.BenchmarkReplaceAll 13492 8519 -36.86%
regexp.BenchmarkAnchoredLiteralShortNonMatch 747 339 -54.62%
regexp.BenchmarkAnchoredLiteralLongNonMatch 599 335 -44.07%
regexp.BenchmarkAnchoredShortMatch 2137 917 -57.09%
regexp.BenchmarkAnchoredLongMatch 2029 917 -54.81%
R=r, r
CC=golang-dev, sam.thorogood
https://golang.org/cl/4820046
