I am trying to use the Quantum Programming language Quipper, and I am running into issues due to the version of GHC I am using:
root#ubuntu:~$ apt-show-versions ghc
ghc:amd64/xenial 7.10.3-7 uptodate
ghc:i386 not installed
As it turns out, 7.10 is the only version that Quipper cannot compile with.
I then discovered that apparently the only way to install Haskell 8.0 was using haskell-stack. Ok, I've never installed something on a stack, so this will go over well.
So I used the instructions on this website to install haskell-stack, then ran the commands:
root#ubuntu:~$ stack setup
root#ubuntu:~$ stack update
root#ubuntu:~$ stack install ghc
The last command returned the following:
Didn't see ghc-8.0.2 in your package indices.
Updating and trying again.
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Selected mirror https://s3.amazonaws.com/hackage.fpcomplete.com/
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Downloading timestamp
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Downloading snapshot
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Updating index
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Updated package list downloaded
Updating package index Hackage (mirrored at https://s3.amazonaws.com/hackage.fpc Populated index cache.
The following package identifiers were not found in your indices: ghc-8.0.2
Perhaps you meant AAI, AAI, AAI, AES, AES, AES, AES, AES, AES, or AES?
So, a quick check again:
root#ubuntu:~$ apt-show-versions ghc
ghc:amd64/xenial 7.10.3-7 uptodate
ghc:i386 not installed
Nope, still 7.10. Tried also to download the package from this website. The package failed to be extracted, so that's a good sign. Rinsed and repeated the above commands, and still nothing. Then I edited the stack.yaml file to say:
resolver: lts-9.14
resolver: ghc-8.0.2
Did absolutely nothing. What step am I missing? Its frustrating when people basically say "the stack does everything for you" and I'm like "what exactly am I supposed to do?"
EDIT
As I said above, downloading the package for 8.0.2 from haskell.org gives fails to extract the archive:
Don't jump into installing the binaries directly. While, as others mentioned, stack isn't the only way, it is certainly one of the easier ones.
So first thing, stack setup actually downloads GHC for you based on the resolver it finds. If you are not in a stack project, it'll default to the global stack config. On the other hand stack install is used for installing packages. That means doing stack install ghc is trying to look for a package on stackage that's called ghc, of which I don't think there are any.
To run the GHC that stack installed, you'll do stack ghc and to get a GHCi session, stack ghci (generally just prefix with stack).
You could also run the general stack exec -- .. to run a command with stack's path variables. E.g. stack exec -- ghci will work here as well, or stack exec -- ghc --version to get the GHC version.
Binary distributions of GHC can be obtained from GHC HQ:
8.0.2 here https://www.haskell.org/ghc/download_ghc_8_0_2.html#binaries
8.2.2 here https://www.haskell.org/ghc/download_ghc_8_2_2.html#binaries
Any suggestion that any one tool is necessary to obtain GHC is wrong.
EDIT: On a nix computer, for example, one can do the following (approx, not tested):
wget https://downloads.haskell.org/~ghc/8.2.2/ghc-8.2.2-x86_64-deb8-linux.tar.xz
tar xJf ghc-8.2.2*
cd ghc*
./configure --prefix=$HOME
make install
If you don't like portable shell and really want to use apt then consider using hvr's PPA which is pretty darn popular.
Related
I'm trying install tidal in command line this way:
cabal install tidal
but it ends with this message:
Warning: You asked to install executables, but there are no executables in
target: tidal. Perhaps you want to use --lib to install libraries instead.
Return of:
cabal install tidal --lib
is:
Resolving dependencies...
Up to date
If I check ghk-pkg list, there is no package tidal
...
Have somebody similar problem or what I'm doing wrong?
My environment is:
Windows 10 Education
Haskell 8.4.3
Cabal 3.2.0.0
Ghc 8.10.1
Thank you for help.
Like Stack for a longer time, Cabal-install does now (as of 3.2) not really install libraries anymore – in the sense of, change the computer's state so that GHC can access the library on it†. Both tools only install executables now. It used to do that for libraries too, but that was stopped with the now default Nix-style builds.
Now (and, really, also already before), the way to use a library is instead to just depend on it, and let Cabal figure out behind the scenes if it needs to be installed. I.e., you add a .cabal file to your .hs source file with build-depends: tidal in it. Then when you say cabal install ., it will first download and install the library before then using it for building your own executable.
†Of course both Stack and Cabal do technically speaking install libraries, just they don't globally register them. I.e., cabal knows where it has installed the library, but you're not really supposed to know about that. It's in the spirit of continuous integration: if your code builds now with the particular state of libraries you happen to have installed, that's not very reliable. If it builds with just those libraries that are explicitly listed in a project file, the chances are much better that future-you (or somebody else) will still be able to use your code on another computer without hours of figuring out what libraries to install first.
cabal install --lib tidal doesn't install the library binaries in a location managed by ghc-pkg. The binaries remain in the Cabal "store".
What it does is to create a plaintext GHC package environment file that is picked up by standalone invocations of ghc and ghci and tells them where to look for the extra libraries.
By default (as mentioned in the docs) this package environment file will be created at ~/.ghc/$ARCH-$OS-$GHCVER/environments/default and will be picked by ghc and ghci invocations made anywhere.
We can also supply an extra --package-env parameter to create the environment file in a local folder, which will only affect ghc and ghci invocations made in that folder. For example:
cabal install --lib --package-env . tidal
cabal projects themselves ignore environment files, as their package environments are constructed from the build-depends section of the cabal file for the sake of reproducibility. But environment files are useful for not having to create a cabal project in the first place, if you only need it for playing with the library in ghci, or if you are compiling simple programs using ghc only.
I'm pretty new to Haskell, and I think I have a fundamental misunderstanding somewhere. When I'm in GHCi (using the ghci command), I can type import System.Random, and it works. I can then generate random numbers.
Next, I make a file called test.hs that contains nothing but one line: import System.Random. I then call the command ghc test.hs and get the following error message:
test.hs:1:1: error:
Could not find module ‘System.Random’
There are files missing in the ‘random-1.1’ package,
try running 'ghc-pkg check'.
Use -v to see a list of the files searched for.
|
1 | import System.Random
| ^^^^^^^^^^^^^^^^^^^^
However, if I go back to GHCi, I can type :load test.hs. This works, and allows me to generate random numbers.
When I run ghc-pkg check, I get only warnings about missing haddock interface files: https://pastebin.com/6a9f0nYZ. From what I understand, this isn't related to the current issue.
Also, when I run ghc-pkg list, random-1.1 is in the list, so random should be installed.
A couple of questions:
Why would GHC and GHCi have access to different imports? Why is the system set up that way? Maybe I just don't understand the relationship between GHC and GHCi.
According to the error message, there are "files missing." How can I figure out which files?
How can I make it so that I can compile Haskell files that use System.Random?
Edit: Both GHC and GHCi are the same version.
$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 8.6.4
$ ghci --version
The Glorious Glasgow Haskell Compilation System, version 8.6.4
Edit: Both ghc and ghci are in /usr/bin/
$ which ghc
/usr/bin/ghc
$ which ghci
/usr/bin/ghci
Update: It looks like this is an Arch Linux peculiarity, not a corrupt package. I've updated my answer accordingly.
GHCi loads "dynamic" versions of modules. By default, GHC links with "static" versions of modules. In particular, when you run:
> import System.Random
under GHCi, it tries to access the file Random.dyn_hi to get interface information for the module. In contrast, when you compile a file with that import statement in it, GHC tries to access the file Random.hi.
You can verify this is the issue by running ghc-pkg field random import-dirs and peeking in the resulting directory. There should be a System subdirectory that usually has two files in it: System.hi and System.dyn_hi. If the former is missing, that's your problem.
Now, it looks like you're probably using Arch Linux. As documented on the Arch Haskell wiki page in the section "Problems with linking", the Arch Haskell community packages (including haskell-random) intentionally omit the static versions of interface files and libraries.
There are several of workarounds given there:
You can use dynamic linking when compiling with GHC. When using GHC directly, this just means passing the -dynamic flag. For Cabal-based projects, instructions are given on that page for modifying your ~/.cabal/config to use dynamic linking for all projects.
You can install the ghc-static and ghc-pristine packages and set up your path and/or Cabal to use the compiler in /usr/share/ghc-pristine/bin/ghc which will maintain its own separate package database that won't interfere with globally installed Haskell community packages, like haskell-random.
You can install ghc-static to get static versions of the base libraries and then run cabal install --force-reinstalls somepackage for all the non-base packages you need. Note that the Wiki notes that this can be tedious and complicated, since you have to manually determine all the package dependencies.
Now, it looks like you already had ghc-static installed, or when invoking GHC you would have also gotten an error about missing files in the base package. You ran cabal install --force-reinstalls random, though as #dfeuer notes, it might have been safer to run:
$ cabal install --force-reinstalls random-1.1
to ensure that the same version was reinstalled.
Anyway, this installed an additional copy of random in your user-specific package directory. If you run:
$ ghc-pkg list
you'll see that random-1.1 is listed both under the global database and user database:
/usr/lib/ghc-8.6.4/package.conf.d
...
random-1.1
...
/home/xxxx/.ghc/x86_64-linux-8.6.4/package.conf.d
random-1.1
and if you run:
$ ghc-pkg describe random
you'll see that it lists the two separate installed versions which is why you now get duplicate fields with ghc-pkg field random import-dirs.
There shouldn't be anything wrong with this. Your user database will take precedence over the global database, so your newly installed version of random will be used when you run GHCi or GHC.
Note that, if you change your mind and want to back out this reinstallation (and maybe try one of the other solutions suggested on the Wiki), you should be able to run:
$ ghc-pkg unregister --user random
Technically, this won't actually remove the package (as the compiled version will still be there under ~/.cabal/lib), but it should otherwise put things back the way they were.
I'm trying to build a project of mine using Stackage lts-13.12.
After Stack was complaining that the version of Cabal was too new, I've tried to install an older version:
cabal --version
cabal-install version 2.2.0.0
compiled using version 2.2.0.1 of the Cabal library
However, when I run stack solver, I get the following error:
Using configuration file: stack.yaml
Using cabal packages:
- ./
Using resolver: lts-13.12
Warning: Installed version of cabal-install (2.4.1.0) is newer than stack has been tested with. If you run into difficulties, consider downgrading.
Using compiler: ghc-8.6.4
Asking cabal to calculate a build plan...
Trying with packages from lts-13.12 and 1 external packages as hard constraints...
The following lines from cabal-install output could not be parsed:
optparse-applicative-0.14.3.0 (via: project-0.1.0.0 project-0.1.0.0) (new
package)
CallStack (from HasCallStack):
error, called at src/Stack/Solver.hs:174:16 in stack-1.9.3-F7FXKCpM3pk5wCtbL9Utvv:Stack.Solver
My questions are:
Why is Stack seeing the newer Cabal? How can I make it see the older one?
Why is Stack incompatible with Cabal 2.4.1.0, when that's the version in the Stackage LTS 13.12?
I'm running Version 1.9.3 of Stack, if that makes a difference.
Stack solver error messages are known to be bad and choke on cabal output. I don't believe this feature is well maintained.
I do wish stack would update its errors and warnings. Sticking with cabal-install-2.4.1.0 is probably the best choice.
Instead of using stack solver, I recommend you force it to use lts-13.12 and then add extra deps by hand to address any issues you encounter. Most of the time stack will helpfully recommend the right extra deps (without using the solver), but you do need to apply some intuition to make sure they are right.
I am trying to install Haskell Platform 2014.2.0.0 from source on Red Hat Enterprise Linux 6.5. I have a functional install of Haskell Platform 2012.4.0.0 and GHC 7.4.2 from two years ago, plus a recently-installed Haskell Platform 2013.2.0.0 and GHC 7.6.3 from JustHub.
I've built GHC 7.8.3 from source, but it keeps coming up with seven failures in the test suite. I have no idea if these test failures are innocuous or not. (The test failures are not relevant to my question, but they may become significant later.)
I unpack the source tarball of 2014.2.0.0, read the README. It says that the way to build this iteration of Haskell is with a shell script, which is invoked:
./platform.sh $PATH_TO_GHC_BINDIST_TARBALL
I don't have a GHC binary distribution tarball. So far as I am able to tell, there is no binary distribution tarball of GHC 7.8.3 for any version of Red Hat Enterprise Linux. I have a built GHC 7.8.3. How do I tell platform.sh -- or whatever is underneath it -- that there is no tarball, and it should just use what's in $PATH? Alternately, how do I pack up my existing install of GHC 7.8.3 so that platform.sh will accept it?
The built GHC does not have a 'cabal' command, so the cabal commands in platform.sh are falling back to $PATH, which I can configure to be either of the other installed versions (2013.2/7.6.3 or 2012.4/7.4.2). It doesn't seem to make a difference: neither one recognizes 'cabal --sandbox'. Both result in complaints that I should run 'cd hptool ; cabal install --only-dependencies', which I've done, repeatedly. platform.sh never gets past that point.
If I run the commands in platform.sh by hand, I get to 'cd hptool; cabal build', which errors out: "cabal-1.16.0.2: Run the 'configure' command first.". But there is no 'configure' command available in the hptool directory.
I'm now stuck. How do I build Haskell Platform 2014 on RHEL 6?
You need to use your GHC sources to make your own "bindist." Directions at https://ghc.haskell.org/trac/ghc/wiki/MakingReleases
I managed to get Haskell Platform installed, and functional. I ended up abandoning platform.sh and just hand-installed all the packages in the Haskell Platform tarball -- and their dependencies -- with manual cabal commands. Along with the broken platform.sh, I ran into many problems on the way.
The ones that I remember:
platform.sh will never succeed if you have the stock Haskell Platform 2013 or previous installed. It wants a cabal that recognizes the '--sandbox' option, and cabal 1.18 doesn't know that option. You must have a newer cabal installed than Haskell Platform 2013 provides. (GHC 7.4 or 7.6 appears to be fine, though.)
I had an existing .cabal and .ghc directory, which had incompatible builds and/or versions of various packages. I deleted both directories numerous times while testing things.
cabal install --global behaves rather differently from the default cabal install --user. .cabal contained something useful after I did 'cabal install cabal-install'. It took two or three tries at that to figure out where the new cabal binary went.
ghc and cabal pick up new libraries in .ghc and .cabal, but not new binaries.
Neither GHC nor cabal install default to --enable-shared, except when something wants it. I had to go rebuild everything before that -- all the way back to GHC 7.8.3 itself -- with --enable-shared once that happened.
haddock is ridiculously tightly bound to the version of GHC it was built with. I had to rebuild it to get --enable-documentation to work for anything built with GHC 7.8.3.
The test packages and the text package are so tightly integrated that they have circular dependencies if you try to do 'cabal install text --enable-tests'. Even after installing the most recent version of text and the test packages, cabal still wouldn't run the text test suite, so I gave up and installed text without testing it.
My default environment includes 'LC_ALL=C'. This trips a known bug in cabal -- apparently in all versions -- that breaks some package builds. To work around it, I had to shift it to 'LC_ALL=en_US.utf8'. I have no idea if the packages affected will work if you have LC_ALL, or any of the other locale variables such as LANG or LC_<anything else>, set to C.
cabal install --global is terribly inconsistent about where packages get stored. We split out individual packages into their own subdirectories, and then build a symlink tree in a known place out of all those subdirectories. So ghc is in its own subdirectory of /usr/sup/ghc-7.8.3; Haskell Platform is in another subdirectory, /usr/sup/haskell-platform-2014.2.0.0. I consistently used --prefix=/usr/sup/haskell-platform-2014.2.0.0 on every 'cabal install' command, but even then, some libraries ended up in /usr/sup/ghc-7.8.3.
Both GHC and Haskell Platform have a dictionary of what's built and where it is -- perhaps as a workaround for the install location inconsistency -- in /usr/sup/ghc-7.8.3/lib/ghc-7.8.3/package.conf.d/package.cache. If that package dictionary isn't world-readable, ghc breaks. What it should do is look at the actual file structure to find things. Given that ghc breaks if the dictionary isn't available, the file shouldn't be called 'cache', as a cache miss shouldn't cause catastrophic failure. Perhaps rename it to 'package-mandatory-dictionary'?
Ultimately, it all installed, but I have to wonder about the damage I did from so much banging my head on the wall.
I've installed ghc 6.12.3, and then the Haskell Platform. I'm trying to compile a test program:
$ ghc test.hs
test.hs:3:0:
Failed to load interface for `Bindings':
Use -v to see a list of the files searched for.
so, naturally, I do
cabal install Bindings
Which works fine, and places the package in ~/.cabal/lib/bindings-0.1.2 The problem is, that when I go to compile again with ghc, it still doesn't find the package I've installed with cabal.
compiling in verbose mode gives:
ghc -v test.hs
Using binary package database: /home/ludflu/ghc/lib/ghc-6.12.3/package.conf.d/package.cache
Using binary package database: /home/ludflu/.ghc/x86_64-linux 6.12.3/package.conf.d/package.cache
As suggested by another stackoverflow user, I tried:
ghc-pkg describe rts > rts.pkg
vi rts.pkg # add the /home/ludflu/.cabal/lib to `library-dirs` field
ghc-pkg update rts.pkg
But to no avail. How to I add the .cabal to the list of package directories to search?
Thank you!
You can check which packages are installed with ghc-pkg list. It may be that you need to either specify the packages to ghc with -package <pkgname> or I believe adding --make to will trigger a chasing down of dependencies, including packages.
Edit: the bindings package is obsolete indeed, see the hackage page. This isn't a package management problem, the only module available is Bindings.Deprecated, which you are perfectly able to load, even though it is an empty module. I believe the relevant parts have been broken out into bindings-<module>, so if you want the bindings functionality you should look to those packages.
http://www.haskell.org/haskellwiki/Cabal-install
One thing to be especially aware of, is that the packages are installed locally by default by cabal, whereas the commands
runhaskell Setup configure
runhaskell Setup build
runhaskell Setup install
install globally by default. If you install a package globally, the local packages are ignored. The default for cabal-install can be modified by editing the configuration file.
I was getting the same error with the runhaskell command. I used the cabal in the directory that had the .cabal file and was able to resolve the error.