[patch] syntax:plain for .hgignore

Matt Mackall mpm at selenic.com
Wed Sep 12 13:19:43 CDT 2007

On Wed, Sep 12, 2007 at 02:01:19PM -0400, Jonathan S. Shapiro wrote:
> On Wed, 2007-09-12 at 12:52 -0500, Matt Mackall wrote:
> > However, there's something that might help without rebuilding Python.
> > Turns out that Python (and Perl) don't actually optimize expressions
> > like foobar|foobaz|fooquux into foo(bar|baz|quux).
> This implies that they are using a backtracking implementation, which
> has negative performance implications.

On the other hand, I think a non-backtracking implementation will generally
have much less expressive expressions and much larger state machines.

> Is the python RE library written in python, or is it a native code
> library?

It's in C.

Mathematics is the supreme nostalgia of our time.

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