[Haskell-cafe] Debugging Haskell code

[Dougal Stanton]

On Sun, Sep 27, 2009 at 9:17 PM, Paul Moore <p.f.moore at gmail.com> wrote:

>
> That's odd, it seems to be saying it's not installed at all! Hmm, no -
> I did a cabal install --user (because Vista doesn't let me do
> site-wide installs), looks like cabal list doesn't pick up user
> installs.
>
> Hmm, cabal install mersenne-random --user didn't do anything, but
> cabal install mersenne-random --user --reinstall did reinstall it, and
> now it seems to work.

To find out what GHC picks up automatically:

$ ghc-pkg list
/home/dougal/lib/ghc-6.10.3/./package.conf:
    Cabal-1.6.0.3, HUnit-1.2.0.3, QuickCheck-1.2.0.0, array-0.2.0.0,
    base-3.0.3.1, base-4.1.0.0, bytestring-0.9.1.4, containers-0.2.0.1,
    directory-1.0.0.3, (dph-base-0.3), (dph-par-0.3),
    (dph-prim-interface-0.3), (dph-prim-par-0.3), (dph-prim-seq-0.3),
    (dph-seq-0.3), extensible-exceptions-0.1.1.0, filepath-1.1.0.2,
    (ghc-6.10.3), ghc-prim-0.1.0.0, haddock-2.4.2, haskell-src-1.0.1.3,
    haskell98-1.0.1.0, hpc-0.5.0.3, html-1.0.1.2, integer-0.1.0.1,
    mtl-1.1.0.2, network-2.2.1, old-locale-1.0.0.1, old-time-1.0.0.2,
    packedstring-0.1.0.1, parallel-1.1.0.1, parsec-2.1.0.1,
    pretty-1.0.1.0, process-1.0.1.1, random-1.0.0.1,
    regex-base-0.72.0.2, regex-compat-0.71.0.1, regex-posix-0.72.0.3,
    rts-1.0, stm-2.1.1.2, syb-0.1.0.1, template-haskell-2.3.0.1,
    time-1.1.3, unix-2.3.2.0, xhtml-3000.2.0.1
/home/dougal/.ghc/i386-linux-6.10.3/package.conf:
    HTTP-4000.0.4, X11-1.4.5, X11-xft-0.3, benchpress-0.2.2.3,
    cairo-0.10.1, colour-2.3.0, cpphs-1.9, darcs-2.2.1,
    data-default-0.2, diagrams-0.2, gd-3000.4.0, gio-0.10.1,
    glib-0.10.1, gtk-0.10.1, hashed-storage-0.3.7, haskeline-0.6.1.6,
    haskell-src-exts-1.1.4, hscolour-1.15, mmap-0.4.1, soegtk-0.10.1,
    split-0.1.1, svgcairo-0.10.1, tagsoup-0.6, terminfo-0.2.2.1,
    terminfo-0.3.0.2, uniplate-1.2.0.3, utf8-string-0.3.4,
    xmonad-0.8.1, xmonad-contrib-0.8.1, zlib-0.5.0.0, zlib-0.5.2.0

You should get everything hanging about, installed system-wide or in
your home directory. I assume this works much the same for Windows.

D