On Tue, May 01, 2007 at 03:45:00PM +0100, Duncan Coutts wrote:
Also, I've still got the platform-independent pre-processed files going back into the src dirs. This isn't nice. The only reason I'm doing that is not to break sdist, however we should probably do that differently anyway.
For example at the moment you need to have done a build for the pre-processed sources to exist in the src dir. Perhaps sdist should just generate the platform independent (and impl-independent) sources directly into the temp dir where we make the tarball. Then during builds we can put them all into the dist/build dir.
Certainly. Building (using specialized preprocessing) ought to be separated from constructing source packages (which requires portable preprocessor output).
The only downside to this is if generating the sources is expensive. Sometimes it is indeed expensive, happy can take quite a while on large grammars and in Gtk2Hs, generating 100+ .hs files with c2hs takes a minute or two on a fast box.
I wonder if optimizing this is worth the increase in complexity (and where does it end -- you need platform-specific versions to avoid the c2hs runs). I was after something less ambitious: including portable preprocessor output in a source package so that people can build it even if they don't have the preprocessor. (Their build may be sub-optimal, though.) That could be done by mapping each suffix to a pair of functions portable :: BuildInfo -> LocalBuildInfo -> Maybe PreProcessor specific :: BuildInfo -> LocalBuildInfo -> Maybe PreProcessor for type Preprocessor = (FilePath, FilePath) -> (FilePath, FilePath) -> Int -> IO () The first one would be used in sdist; if the portable preprocessor is available, add its output to the source package. The second function would be used in build; if the specific preprocessor is unavailable, copy the .hs version of the module (which, if present, should be portable preprocessor output). (Presumably if the portable preprocessor is available the specific one is too, but we don't need to use that.) BTW, since you're now collecting Haskell files in a single build hierarchy, you could copy the main-is to Main.[l]hs in that hierarchy, and also generate the Paths module directly there instead of in autogen. BTW2, building under Hugs will now require two directories under dist: one for the (build-specific) preprocessor output and another for the build outputs, which may be obtained from those using cpphs and ffihugs.