how to reuse cabal compiled modules when using ghci

Question

I have a fairly large haskell project, and running ghci on some files can require compiling dozens or hundreds of modules before it gets to a prompt, which can take a number of minutes. I'm using cabal, and so I generally have already compiled object files under dist/. But ghci only looks for .o files next to the source .hs files; it does not know about cabal's dist/. Is there any simple and good way to make ghci load those object files rather than recompiling everything on its own?

I'm asking for a simple and good way, because I have complicated and ugly ways to do it. :) For example, this will make ghci reuse the cabal compiled modules. I came up with this command line by copying, and modifying the way cabal runs ghc, ensuring that it sets everything the same as the last cabal build, which is necessary to make sure ghci will load the modules.

ghci -package-conf dist/package.conf.inplace -i -idist/build/git-annex/git-annex-tmp -i. -idist/build/autogen -Idist/build/autogen -Idist/build/git-annex/git-annex-tmp -optP-include -optPdist/build/autogen/cabal_macros.h -odir dist/build/git-annex/git-annex-tmp -hidir dist/build/git-annex/git-annex-tmp -stubdir dist/build/git-annex/git-annex-tmp -XHaskell98 dist/build/git-annex/git-annex-tmp/Utility/libdiskfree.o dist/build/git-annex/git-annex-tmp/Utility/libmounts.o

Seems to me it should be possible for a "cabal ghci" to calculate this command line and run it, or perhaps there is a tool I don't know of that already does so.

Answer 1

您可以将odir和ohi选项设置为指向cabal构建目录，如下所示： http ： //www.haskell.org/ghc/docs/7.6.1/html/users_guide/separate-compilation.html#output-files