-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/6/10 23:09 , wren ng thornton wrote:
On 11/6/10 6:20 AM, Reiner Pope wrote:
I was aware of this condition, but I'm not precisely sure it addresses my requirements. When you run "cabal install some-package", cabal reads all version constraints listed in the "build-depends" field, and chooses which versions of which packages to download from Hackage in order to satisfy these constraints.
I want to expose my dependency on a particular version of ghc to cabal's constraint satisfier. The end result I want is that when you type "cabal install hmatrix-static" with ghc-6.12 installed, then cabal chooses hmatrix-static-0.3; and when you type "cabal install hmatrix-static" with ghc-7.0 installed, then cabal chooses hmatrix-static-0.4.
Clients of hmatrix-static would have to say
if impl(ghc >= 7.0) Build-Depends: hmatrix-static == 0.4.* else Build-Depends: hmatrix-static == 0.3.*
in order to pull in the right dependency for themselves.
In order to get the behavior you're after, though, is trickier business. Since every version of GHC ships with a different version of base, you'll have to make use of that knowledge such that users of ghc-7.0 with base-5 will get hmatrix-static-0.4 whereas users of ghc-6.12 with base-4 will get hmatrix-static-0.3
Don't you just rerelease 0.3.x (bump the sub-version) with a dependency on base < 5, and release 0.4 with base = 5, and let Cabal work out the above Build-Depends for itself? - -- brandon s. allbery [linux,solaris,freebsd,perl] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.10 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkze5FUACgkQIn7hlCsL25XnkACZAULQcjlaAxsClFxhQRsHcuRX NBkAn2cbZ4FD1+Qtu1qsB7f9mXvPHjMt =Zt6h -----END PGP SIGNATURE-----