I have a package.yaml file like:
name: ...
version: ...
...
flags:
strict: ...
description: ...
...
dependencies:
...
...
Mostly typical package.yaml file. And one of the dependencies uses a library (so it's a transitive dependency) which has flags (one of them is use-pkg-config flag).
How to turn on this flag? I tried:
pkg-config-dependencies: that-library
Also I tried to add a GHC option:
...
ghc-options:
...
-fuse-pkg-config
and to add flags: section to library:, it seems it does not work because I see in the compilation console output:
......... -f-use-pkg-config ....
and not -fuse-pkg-config, so I suppose it does not work. How to add a flag for such dependency (it's transitive - I don't know it matters or not) in package.yaml?
Flags can be specified in project-level configuration files, stack.yaml or cabal.project.
-- cabal.project
package my-dependency
flag: +use-pkg-config
# stack.yaml
flags:
my-dependency:
use-pkg-config: true
Documentation:
cabal https://cabal.readthedocs.io/en/stable/cabal-project.html#cfg-field-flags
stack https://docs.haskellstack.org/en/stable/yaml_configuration/#flags
Related
I want to build the haskell bindings for z3 in a Cabal project, the following is the minimum (faulty) example:
Using a project initialized by cabal init:
test/
- Main.hs
- Setup.hs
- CHANGELOG.md
- test.cabal
With modified test.cabal:
cabal-version: 3.0
name: z3-test
version: 0.1.0.0
extra-source-files: CHANGELOG.md
executable test
main-is: Main.hs
build-depends: base >=4.14 && <4.15
, z3 ^>=408.2
default-language: Haskell2010
Z3 binaries are located at C:\z3-4.8.5-x86-win.
Z3-bindings are installed:
cabal v1-install z3 --extra-lib-dirs=C:/z3-4.8.5-x64-win/bin --extra-include-dirs=C:/z3-4.8.5-x64-win/include -v3
All the requested packages are already installed:
z3-408.2
Use --reinstall if you want to reinstall anyway.
Now building the project using:
cabal v2-build --extra-lib-dirs=C:/z3-4.8.5-x64-win/bin --extra-include-dirs=C:/z3-4.8.5-x64-win/include -v3
Results in the error:
Build profile: -w ghc-8.10.2 -O1
In order, the following will be built (use -v for more details):
- z3-408.2 (lib) (requires build)
- z3-test-0.1.0.0 (exe:test) (first run)
Starting z3-408.2 (lib)
Failed to build z3-408.2. The failure occurred during the configure step.
Build log (
C:\cabal\logs\ghc-8.10.2\z3-408.2-1722a25655334afbca91ac935f14ff0d20ccf8c4.log
):
Configuring library for z3-408.2..
cabal.exe: Missing dependency on a foreign library:
* Missing (or bad) header file: z3.h
* Missing (or bad) C library: z3
This problem can usually be solved by installing the system package that
provides this library (you may need the "-dev" version). If the library is
already installed but in a non-standard location then you can use the flags
--extra-include-dirs= and --extra-lib-dirs= to specify where it is.If the
library file does exist, it may contain errors that are caught by the C
compiler at the preprocessing stage. In this case you can re-run configure
with the verbosity flag -v3 to see the error messages.
If the header file does exist, it may contain errors that are caught by the C
compiler at the preprocessing stage. In this case you can re-run configure
with the verbosity flag -v3 to see the error messages.
cabal.exe: Failed to build z3-408.2 (which is required by exe:test from
z3-test-0.1.0.0). See the build log above for details.
How can I build a project with the z3 bindings?
Note that:
GHC version = 8.10.2
Cabal version = 3.2.0.0
I can only use cabal
Using cabal install ... or cabal v2-install ... results in Cannot build .. z3 because none of the components are available to build:
I have projects compiling with cabal build (but using hpack for the convenience). For some reason, I would like to compile them with stack build. What goes into a minimal stack.yaml file?
The stack documentation gives details what goes into such a file, but does not show a minimal (or any, as much as I can see) example. I fear to use stack init on an existing project for unintended consequences.
What is a small example from which to go?
A minimal stack.yaml:
resolver: lts-19.16 # for ghc 9.0.2 newest lts
packages:
- .
A not-so minimal skeleton from which to expand:
resolver: lts-19.16 # for ghc 9.0.2 newest lts
packages:
- .
extra-deps: # include here other local packages
ghc-options:
"$everything": -haddock # to produce documentation with haddock
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 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'm trying to set up a build environment for wxHaskell using Nix and Stack.
I've installed wxWidgets-3.0.2 through nix. This is the relevant portion from by .cabal file
executable hellowx-exe
hs-source-dirs: app
main-is: Main.hs
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends: base
, hellowx
, wx
, wxc
, wxcore
, wxdirect
and the stack.yaml file
resolver: lts-5.0
extra-deps:
- wx-0.92.2.0
- wxc-0.92.2.0
- wxcore-0.92.2.0
- wxdirect-0.92.2.0
I tried adding
nix:
enable: true
packages: [wxwidgets]
but that wasn't the right way apparently.
So I got rid of the nix part in the .yaml file and tried the command $ stack --nix build which resulted in failure. The log file said
[1 of 1] Compiling Main ( /run/user/1000/stack8847/wxc-0.92.2.0/Setup.hs, /run/user/1000/stack8847/wxc-0.92.2.0/.stack-work/dist/x86_64-linux-nix/Cabal-1.22.5.0/setup/Main.o )
Linking /run/user/1000/stack8847/wxc-0.92.2.0/.stack-work/dist/x86_64-linux-nix/Cabal-1.22.5.0/setup/setup ...
Error: wx-config not found, please install wx-config before installing wxc
However I do have wx-config and wxwidgets installed through nix. The build process can't find it for some reason. What can I do to set up this build environment? Is there a way to direct the build process to look in the directory containing wx-config? I can't figure out why it can't find it. Its in the PATH.
Ok, I figured it out. I was adding the wrong "attribute name". Here is the correct stack.yaml file
# at this point in time nix supports lts-5.0
resolver: lts-5.0
packages:
-'.'
extra-deps:
- wx-0.92.2.0
- wxc-0.92.2.0
- wxcore-0.92.2.0
- wxdirect-0.92.2.0
# wxwidgets-3.0.2 has the attribute name wxGTK30
# you also need zlib, mesa_noglu and x11
nix:
enable: true
packages: [zlib, wxGTK30, mesa_noglu, x11]
That seems to build everything properly, and I was able to build a minimal window from here (minimal.hs)