Adding System.FilePath

[ArtemGr]

Bulat Ziganshin <bulat.ziganshin <at> gmail.com> writes:
> i think that it will be degradation because new base version will be
> not available for users before 6.8 arrives and then it will be hard to
> change this interface without breaking compatibility with existing
> code. otoh, providing it as separate library solves these problems. if
> developer is too lazy to cabalize his code, its not the cause to add
> his module to the base. let's wait for someone who will be more eager

With FPS i did use the library with GHC 6.4 by fetching and installing it via
Cabal, and with GHC 6.6 it is shipped (thanks for that!). The same might be done
to FilePath: those who need it before GHC 6.8 will fetch and install it manually
(or via hackage), and those who use GHC 6.8 will have it out of the box.

P.S.
I think it should be possible to install the fresh version of FPS and GHC
compiler should be smart enough to link both the old version (if it is required
by some other part of the base) and the new one...

> otoh, providing it as separate library solves these problems.

I don't think so. If you use a complex library which uses the old FilePath API,
you usually stuck with the old FilePath API.
For example, HAIFA (http://www.dcs.shef.ac.uk/~simonf/HAIFA.html) requires SYB3,
which i couldn't find on the web, so, it being a separate package from the base
didn't solve the problem.