I love the idea of well-integrated expressions etc being available for string handling and in tools. The tricky bit is that ‘well-integrated’.

If at all possible it should be done without any extra primitives. Unless we have a convincing use case for such string handling needing to be frequently done and very fast I don’t see much value in adding more C code. With Cog and SISTA making the system so much faster we have to consider the possibility that doing all the marshalling, converting, stack fapping, c-code calling, returning, re-converting may take more time than leaving it to Smalltalk.
I suppose the counter-argument would be that using a standard library guarantees correct results. Except of course we have a lot of experience with supposedly standard libraries being utterly screwed. Jpeg libraries, anyone? ALSA?

As for the actual expression grammar, I imagine most people would be assuming the unix regexp form which has the advantage that a lot of people are familiar with it. And the disadvantage that a very large number of people are not.

tim
--
tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
Useful random insult:- Went to the dentist to have his cranial cavity filled.