installing dependencies in haskell - haskell

I was trying to install cabal-dev in my mac. After cloing, I tried to run ./bin/build. to get this error message.
cabal: cannot configure cabal-dev-0.9.1. It requires MonadRandom ==0.1.*, tar
==0.3.*, test-framework >=0.3 && <0.6 and test-framework-hunit >=0.2
There is no available version of MonadRandom that satisfies ==0.1.*
There is no available version of tar that satisfies ==0.3.*
There is no available version of test-framework that satisfies >=0.3 && <0.6
There is no available version of test-framework-hunit that satisfies >=0.2
What's wrong with this? How do I install the dependency files in Haskell?
I downloaded and installed from Haskell platform.

You don't have to use that build script; you can install cabal-dev just by running cabal install cabal-dev, which will automatically download and install cabal-dev and its dependencies.
But if you do want to use it, try cabal install --only-dependencies in cabal-dev's source directory first (the one with cabal-dev.cabal in it). That script's purpose is to avoid avoid installing into the global and user package databases — basically, it uses the same sandboxing cabal-dev itself does. It's probably not worth the effort, since cabal-dev installs just fine like every other program.

Issue the command cabal install cabal-dev. It will resolve the dependencies for you, assuming you have the standard cabal dist.

Related

Upgrade package dependencies using Cabal

I have a script that deploys a Haskell program once a day. It currently does:
cabal update
cabal install --only-dependencies
cabal configure
cabal build
Which ensures it has the latest package index list, upgrades any dependency whose lower bound in the project.cabal has changed, and builds the code.
However, I'd really like to upgrade any dependency that has a new suitable version.
I tried adding --upgrade-dependencies but that refused to upgrade anything because it would break existing packages.
I tried combining that with --force-reinstalls, but it installed a new version of template-haskell (not a good idea) and things like QuickCheck would no longer compile.
What is the right way to upgrade packages automatically?
You could use cabal new-build and if you only want to upgrade most dependencies then freeze the few you wish to hold constant in a cabal.project.freeze file.
cat <<EOF >cabal.project.freeze
constraints: template-haskell == 2.13.0.0
EOF
And
cabal update
# Perhaps rm -rf dist-newstyle if you want a completely fresh build
cabal new-build --upgrade-dependencies
Upgrade to Cabal 2.0.0.0 or above.
From Cabal 2.0.0.0 it no longer upgrades template-haskell, as per the changelog:
Made the 'template-haskell' package non-upgradable again (#4185).
So --upgrade-dependencies --force-reinstalls works with newer versions.

For cabal, what does only-dependencies flag mean?

I'm fairly new to Haskell, and upon seeing this flag, e.g. in this dockerfile, I can't ever seem to find an explanation for what it does. "Install only the dependencies necessary to build the given packages," in the cabal help install doesn't say much to me.
If I'm not building inside a docker container, I use sandboxes. Is this flag applicable to either of these situations?
For cabal, what does only-dependencies flag mean?
It can be spelled as both --dependencies-only and --only-dependencies and it simply means that it will install all, and only, the dependencies the specific package requires (without installing or building the packages themselves). Note that by default tests and benchmark dependencies will not be installed; for them you need to add --enable-tests and --enable-benchmarks respectively.
Is this flag applicable to either of these situations?
Yes, this can be used just fine with cabal sandboxes as well as without.
What's then the difference between it and simply running cabal install, which has worked for me so far?
cabal install will install both those dependencies and the packages themselves. Same for cabal build. cabal install --only-dependencies will only install the dependencies those packages require.

Failing to install Haskell uniplate library

I am trying to install Elm and the instructions are to install Haskell and then
sh> cabal update
sh> cabal install cabal-install
sh> cabal install -j Elm elm-repl elm-reactor elm-get
When I do, the cabal-install installation installs text-1.2.0.0 which conflicts with the text-1.1.0.0 which uniplate requires so uniplate and its dependents fail to install. Text-1.1.0.0 is installed and present but is rejected in favour of text-1.2.0.0, even though the target needs text-1.1.0.0.
Is there a way to insist that cabal use text-1.1.0.0?
Is there a way to get text-1.1.0.0 and text-1.2.0.0 to co-exist?
Is there a way to convince uniplate that it can accept text-1.2.0.0?
Or a way to make uniplate (or cabal) believe that version text-1.1.0.0 is actually installed? Would that even work?
When I explicitly try to install version 1.1.0.0 of text, I am told that a reinstall would break other packages. Apparently it is a downgrade and not a co-installation. cabal does not seem to have an option to allow to me install two versions of the same library at the same time.
If I uninstall Haskell and all the libraries and then re-install Elm (without installing cabal-install so I don't get text-1.2.0.0 installed so there is no clash), I get 100 or so lines of
package aeson-0.7.0.4-8f84b14cc682e4c9b009352420076a45 is unusable due to missing or recursive dependencies:
attoparsec-0.10.4.0-ec2d0a330db1f6e3a6a3b79471a403ef hashable-1.2.2.0-45bd22df8c4ead6b3a7fb1d08bb07f7d mtl-2.1.3.1-8bcc0591131896cfc8761a93703d4c61 scientific-0.2.0.2-5e275f5d96527da6dc1f05642692a484 syb-0.4.1-be94ebe67c3607f5df1dfcc1906f5d5c text-1.1.0.0-9bd69e9ace700e05fb08e463086bc383 unordered-containers-0.2.4.0-69836b34d13649bcfacc8fb0c9f53e64 vector-0.10.9.1-c550551354bc7c2b5a1d261f39b2f3f4
package aeson-pretty-0.7.1-5dc26d5a4560afe110e90283479a1251 is unusable due to missing or recursive dependencies:
aeson-0.7.0.4-8f84b14cc682e4c9b009352420076a45
text-1.1.0.0-9bd69e9ace700e05fb08e463086bc383
unordered-containers-0.2.4.0-69836b34d13649bcfacc8fb0c9f53e64
vector-0.10.9.1-c550551354bc7c2b5a1d261f39b2f3f4
package asn1-encoding-0.9.0-94e9066cccf7ead73bee5ae4aa982071 is unusable due to missing or recursive dependencies:
mtl-2.1.3.1-8bcc0591131896cfc8761a93703d4c61
package asn1-parse-0.9.0-af4efc4777a8a0d9d19a626d5e4b08ff is unusable due to missing or recursive dependencies:
asn1-encoding-0.9.0-94e9066cccf7ead73bee5ae4aa982071
mtl-2.1.3.1-8bcc0591131896cfc8761a93703d4c61
text-1.1.0.0-9bd69e9ace700e05fb08e463086bc383
I have no idea at all how in resolve this or where to even try. Has anybody trod this path before and do you have any advice or pointers?
Thank you.
Edit
Installing in a sandbox changes the outcome only by degrees: text-1.1.0.0 does not clash with text-1.1.0.0 but still can not be loaded (despite being installed) and still remains the unsatisfied dependency.
blaze-builder is first to fail with cannot satisfy -package-id text-1.1.0.0-9bd69e9ace700e05fb08e463086bc383 yet the same log earlier stated [_12] trying: text-1.1.0.0/installed-9bd... (dependency of Elm-0.13) without apparent error or complaint.
cabal list shows both text-1.1.0.0 and text-1.2.0.0 as installed.
Installing blaze-builder separately looks the same. Dependency resolution shows
[_56] trying: blaze-builder-0.3.3.4 (user goal)
[_57] next goal: text (dependency of blaze-builder-0.3.3.4)
[_57] trying: text-1.1.0.0/installed-9bd...
[_58] done
All looks good but later, same log has
<command line>: cannot satisfy -package-id text-1.1.0.0-9bd69e9ace700e05fb08e463086bc383
(use -v for more information)
The ghc command line already had the -v flag and trying to re-run the command line copied from the log, with more -vs, gives an error with "can't find a package database at
dist/dist-sandbox-ad0bcd57/package.conf.inplace".
No package.conf.inplace seems to exist.
Further edit
On the Elm install page is a link to a BuildFromSource.hs script that is also supposed to work installing Elm. In the time that it took for that script to run and fail to work, I managed to install leiningen, node, npm, grunt and Clojure. I am now further along the road to getting Clojurescript installed in about 20 minutes than I am in getting Elm installed in nearly a week.
Elm looked really interesting but it is playing way too hard to get.
Thanks again to everyone who tried to help.
* Edit *
I finally got it.
Every executable installed by the installer at http://elm-lang.org/Install.elm caused a segfault.
The "Build from source" option at the same page did not work because the dependencies either stepped all over each other or could not get themselves straight in the first place.
The ghc at http://new-www.haskell.org/downloads/osx needs a later version of Mac OS than I have. (A link to older versions would not have gone astray.)
The solution (and it is obvious in retrospect) was to port install haskell-platform and port install hs-cabal-install and cabal install Elm .... I did have to run one of those installers twice because it could not find hackage.haskell.org (How is that a 'user' error?) but my hello-world.elm now compiles.
Thank you all again.
It looks like some dependency issues with elements you already have installed. You will probably need to install it in a sandbox.
First, update to the latest version of cabal:
$ cabal update
$ cabal install cabal cabal-install
Next, make sure you have the installed version of cabal on your $PATH.
$ which cabal
> /path/to/cabal/bin/cabal
If it says something like /usr/bin/cabal you will need to export cabal to be on your $PATH. For me this is `/home/username/.cabal/bin
$ export PATH=/path/to/cabal/bin/cabal;$PATH
Run which cabal again and ensure it is pointing to that path.
Now that you have the latest version of cabal. Run the following:
$ mkdir elm
$ cd elm
$ cabal sandbox init
This will initialize a sandbox where dependencies are completely independent of your other installs. Within this directory, you should be able to install the elm platform by running:
$ cabal install Elm elm-repl elm-reactor elm-get
These will be installed in a sub-directory called .cabal-sanbox/bin/ For convenience, you will probably want to add this to your $PATH so you can run the executables from any directory.
Hope this helps!

How do you install packages/libraries without Cabal or Cabal-Install?

I'm trying to set up Haskell from scratch, on Ubuntu 11.04, without using the outdated Debian repository or Haskell-Platform.
I've installed GHC-7.0.4 from source with no problem, and now need to install Cabal (which appears to already be included in GHC in /usr/local/lib/ghc-7.0.4/Cabal-1.10.2.0) and Cabal Install.
The latter specifies several dependencies (parsec and network), each of which has several dependencies of their own (mtl, text, etc).
What's the command to install these packages, that I downloaded from hackage in tar.gz form?
Unpack, then runhaskell doesn't work.
I see Setup.lhs, but it's not clear what that's for or how to use it.
Most of the Haskell documentation I've found assumes you've installed from a repo or Haskell-Package and doesn't really explain this well.
cabal-install has a shell script that does this. If you download it from hackage and install it, you can start bootstrap.sh to install cabal-install. You can then use it to install other packages.
There are two different packages: Cabal and cabal-install. Cabal is a library, and cabal-install is an executable named cabal.
To install a package, cabal-install is an optional convenience wrapper around Cabal, but Cabal is required.
According to http://hackage.haskell.org/trac/ghc/wiki/Commentary/Libraries , Cabal is a 'zero-boot' package, so when you build GHC, Cabal and its dependencies are built for you automatically.
You can use ghc-pkg executable to check which packages are already installed:
# ghc-pkg list
Check if Cabal is in the list after you build GHC. If yes, you can install more packages without cabal-install using this documentation:
http://haskell.org/haskellwiki/Cabal/How_to_install_a_Cabal_package
I suggest you to install cabal-install first, and then install everything else using cabal-install executable. A usual commandine for global installation is this:
# runhaskell Setup configure
# runhaskell Setup build
# sudo runhaskell Setup install
Unpack a package tarball and run the commands in the folder with Setup.hs or Setup.lhs files. Note that a per-user non-root installation is also supported - Use runhaskell Setup configure --user
When you install cabal executable and its dependencies this way, use cabal install {package-name} to install more packages.
Note that Haskell Platform exists mostly because of the pain of installing cabal-install by yourself.

Haskell Cabal regenerate documentation for all installed packages

How can I generate and install documentation for all locally installed cabal packages? I turned on the documentation flag in ~/.cabal/config which means that all newly installed packages will have documentation also generated. But how to generate documentation for all already installed packages?
Is there a way to automatically cabal install --reinstall all already installed packages? And more importantly, is that a good idea?
If you have a recent-ish version of cabal-install (>= 0.10, I think), you can try doing
$ cabal install --reinstall --upgrade-dependencies world
Unfortunately, it didn't work in my case:
$ cabal install --dry-run --reinstall world
Resolving dependencies...
cabal: cannot configure Agda-2.2.10. It requires haskell-src-exts >=1.9.6 &&
<1.10
For the dependency on haskell-src-exts >=1.9.6 && <1.10 there are these
packages: haskell-src-exts-1.9.6. However none of them are available.
haskell-src-exts-1.9.6 was excluded because haskell-src-exts-1.11.1 was
selected instead
haskell-src-exts-1.9.6 was excluded because hlint-1.8.12 requires
haskell-src-exts ==1.11.*
If you bump into an error like this, you can try manually editing the ~/.cabal/world file.
Please note that cabal install --only-dep --reinstall does not work.
If you are using a sandbox, you can do
cabal sandbox delete
cabal sandbox init
cabal install -j --only-dep --enable-documentation
The -j option allows it to build in parallel.
You could try something like this in bash.
for pkg in `ghc-pkg list --simple`
do
cabal install $pkg --reinstall
done
But I really don't know, whether it's a good idea.

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