I am trying to use EuterpeaLite (https://github.com/Euterpea/EuterpeaLite), but it is not on Hackage.
I imported it like such import EuterpeaLite as EL and I added it to my cabal file like this:
build-depends:
base >=4.7 && <5
, postgresql-simple
, EuterpeaLite
But when I run stack build or stack ghci, I get this error:
Error: While constructing the build plan, the following exceptions were encountered:
In the dependencies for engine-0.1.0.0:
EuterpeaLite needed, but the stack configuration has no specified version (no package with that name found, perhaps there
is a typo in a package's build-depends or an omission from the stack.yaml packages list?)
needed since engine is a build target.
Some different approaches to resolving this:
Plan construction failed.
Is there a special process for non-Hackage packages?
I used the following procedure.
Create a new stack project stack new myproject --resolver=14.27. I needed to specify an older resolver, since EuterpeaLite wouldn't build with lts-15.3
In the myproject directory, add the following lines to stack.yaml:
extra-deps:
- git: https://github.com/Euterpea/EuterpeaLite.git
commit: 5fe2d129bd3087dd78c0feaf4d35fc03ffd36215
Also in the myproject directory, I added the following dependency to package.yaml:
dependencies:
- base >= 4.7 && < 5
- EuterpeaLite # <- added this line
Ran stack build in the myproject directory.
As you noted, instead of using package.yaml, you could change your .cabal file.
Related
I am trying to add dependency of gtk2hs-buildtool to my Haskell project but following error while building stack.
In the dependencies for TicTacToe-0.1.0.0:
gtk2hs-buildtools needed, but the stack configuration has no specified version (latest matching
version is 0.13.5.4)
needed since TicTacToe is a build target.
TicTacToe.cabal file:
library
exposed-modules:
TicTacToeEngine
other-modules:
Paths_TicTacToe
hs-source-dirs:
src
build-depends:
base >=4.7 && <5,
gtk2hs-buildtools
default-language: Haskell2010
If you are using stack tool you shouldn't touch the <packagename>.cabal file. stack is in charge to generate it from package.yaml. Despite of the fact that is a common practise to modify the <packagename>.cabal, development workflow will be easier if you don't.
The files you are interested in (and the ones that stack tool uses) are the stack.yaml and package.yaml.
In stack.yaml you should see an entry called resolver: lts-XX.XX. That means that your dependencies version are managed such that they match those in the given lts (a.k.a. snapshot). You can go to https://www.stackage.org/, click on your lts version and search for the gtk2hs-buildtools package to get the right version for your project (example: lts-12.26 uses gtk2hs-buildtools-0.13.4.0). In your package.yaml, in the dependencies section write the entry entry - gtk2hs-buildtools
From lts-13.11 and above gtk2hs-buildtools is not available in stackage, so you need to add it as an extra-dep. in the stack.yaml, in the section extra-dep add the following entry gtk2hs-buildtools-0.13.4.0 (or the version number you'd like to use). Then add in the package.yaml and entry gtk2hs-buildtools. It is necessary to add the entry in both files. Refer to stack docs o understand why.
Just to ensure you can build your project, your files should something look like the following:
if using resolver above or equal to 13.11
stack.yaml
resolver: lts-13.11
extra-deps:
- gtk2hs-buildtools-0.13.4.0
package.yaml
dependencies:
- base
- gtk2hs-buildtools
if using resolver below 13.11
stack.yaml
resolver: lts-12.26
extra-deps:
package.yaml
dependencies:
- base
- gtk2hs-buildtools
I'm trying to set up a Haskell project with Stack. I have created a project: stack new project1 and added the suggested dependency (acme-missile) just to see how it works.
extra-deps:
- acme-missiles-0.3
But when I try to invoke launchMissile in the Main it won't work. I get
Error:(3, 1) Could not find module ‘Acme.Missiles’
Use -v to see a list of the files searched for.
|
3 | import Acme.Missiles
| ^^^^^^^^^^^^^^^^^^^^
What is the problem? What am I missing?
EDIT
When I run stack solver I get this:
Using configuration file: stack.yaml
Using cabal packages:
- ./
The following changes will be made to stack.yaml:
* Dependencies to be deleted
extra-deps:
- acme-missiles-0.3
To automatically update stack.yaml, rerun with '--update-config'
Isn't that strange? Like it thinks my dependency is not needed?
You'll need to add the dependency to project1.cabal as well:
build-depends:
base >=4.7 && <5
, project1
, acme-missiles
Alternatively, on newer versions of Stack, it looks like you should use package.yaml instead:
dependencies:
- base >= 4.7 && < 5
- acme-missiles
I can't say that I have deep knowledge of how this works, but if I understand it correctly, the main file where you're supposed to add dependencies is in the .cabal or package.yaml file. The extra-deps field in stack.yaml is where you can indicate if you have dependencies that deviate from the LTS that you currently use.
I have mylib library package and myapp application. I want to use Cardinality package in mylib which is available only as tarball. So, I added to mylib stack.yaml:
packages:
...
- location: https://hackage.haskell.org/package/Cardinality-0.2/Cardinality-0.2.tar.gz
extra-dep: true
Then I add to mylib's cabal file:
build-depends: ...
, Cardinality
And it's compilable. Now I'm trying to build myapp tool which depends on mylib:
packages:
...
- '../mylib'
But I get error:
Error: While constructing the build plan, the following exceptions were encountered:
In the dependencies for mylib:
Cardinality must match -any, but the stack configuration has no specified version (latest matching version is 0.2)
needed since mylib is a build target.
Some potential ways to resolve this:
* Recommended action: try adding the following to your extra-deps in /home/XXXX/prj/myapp/stack.yaml:
- Cardinality-0.2
* Set 'allow-newer: true' to ignore all version constraints and build anyway.
* You may also want to try using the 'stack solver' command.
Plan construction failed.
So, how to add Cardinality tarball to mylib package in right way?!
I am working on my first major Haskell application, and want to add mockery to create disposable test WAI threads. Importing mockery and running stack test resulted in the compiler error:
Failed to load interface for ‘Test.Mockery.Directory’
It is a member of the hidden package ‘mockery-0.3.5’.
Perhaps you need to add ‘mockery’ to the build-depends in your .cabal file.
Use -v to see a list of the files searched for.
So, I added mockery to my cabal file under test dependencies. However, when I run stack build or stack test mockery is automatically removed from the cabal file.
I have also tried listing mockery-0.3.5 under extra-deps in the stack.yaml file. This unsurprisingly didn't work, since mockery is part of my lts, and extra deps is for packages outside of lts.
How can I get stack to recognize that mockery should be included as a dependency to to project?
Here is my stack.yaml:
flags: {}
ghc-options:
! '*': -Wall
packages:
- .
extra-deps: [
]
resolver: lts-9.5
I'm using stack version 1.5.1
I imagine this is a stupid build issue and look forward to confronting my obvious oversight.
In stack.yaml you declare the Stackage LTS version, a curated list of hackage dependencies that you want to depend on. You can also depend on local packages and packages in git that are not in Hackage. You may also change the versions of the packages in LTS as long as they respect the constraints of the other dependencies.
package.yaml is the build file. Any packages you want to import directly in your Haskell code must be declared in here as dependencies, even if they are explicitly declared in the stack.yaml.
Finally, when you see It is a member of the hidden package, that means that one of your dependencies is using that package, but it is not declared as a dependency in your build file.
I want to use reactive-banana in my new Haskell project. I never used cabal-install or stack before. I created a directory and initialized project files in it using stack new. I see now 2 files in the directory: new-template.cabal and stack.yaml.
How do I set dependencies and make sure they are downloaded and compiled?
At first I tried to add - reactive-banana-0.8.0.2 in stack.yaml under extra-deps:, but both stack build and stack solver didn't download it. Then I augmented a part called library in new-template.cabal to this:
library
hs-source-dirs: src
exposed-modules: Lib
build-depends: base >= 4.7 && < 5
, reactive-banana >= 0.8
default-language: Haskell2010
Every time I tried to run stack build, it crashed with an error and suggestion to add some package to stack.yaml under extra-deps:, and this happened three times until finally all packages installed, and I could import them in stack ghci REPL.
So my question is, what is the idiomatic way to use stack? Which of these 2 files should I use to specify dependencies and other project metadata? What is the sample workflow of an average Haskell developer with stack?
When using stack I generally don't put any versions bounds in my .cabal file. I let the resolver and extra-deps setting in the stack.yaml file determine which versions of packages to select.
Here is a stack.yaml file which brings in reactive-banana-0.8.1.2:
flags: {}
packages:
- '.'
extra-deps:
- reactive-banana-0.8.1.2
- psqueues-0.2.0.2
resolver: lts-2.17
In my .cabal file I just have:
build-depends: base >= 4.7 && < 5, reactive-banana
The reactive-banana version is pinned by the stack.yaml file.
If you want to use GHC 7.10 change the resolver to something like nightly-2015-06-17.
I determine the extra-deps iteratively, by just running stack build and adding whatever dependencies are missing to the stack.yaml file until all dependencies are satisfied.
You will only need to do this with packages which are not in Stackage - like reactive-banana. A great many of commonly used packages are in Stackage and their versions will be determined by the resolver setting.
In the default configuration, stack works with two package databases: a centralised per-user one and a project-specific one. The centralised database only pulls packages from Stackage, a subset of Hackage with known-to-be-compatible packages, while you can put whatever you want on the project-specific database. All packages you use must be in the cabal file, but those not on Stackage (that is, the ones that will go to the project-specific database) must also be listed in the extra-deps section of stack.yaml. reactive-banana is not on Stackage, so you need to add it to stack.yaml, like this:
# etc.
extra-deps:
- reactive-banana-0.8.1.2
# etc.
stack solver can fill in the extra dependencies in stack.yaml for you.