ihaskell VS ghcid

More info: https://github.com/gibiansky/IHaskell/issues/1251

I'm stymied trying to import a package. It's Graphics.Matplotlib. (See here.) I'm wanting it for my IHaskell, but when I add it to the IHaskell stack.yaml

That looks like a generic front-end error for when the back-end is unavailable, the back-end error should be more informative, but I don't know where exactly you can find it. At this point it might make sense to open an issue on the issue tracker of IHaskell, they will be able to give you more useful answers.

​ curl -sSL https://get.haskellstack.org/ | sh git clone https://github.com/gibiansky/IHaskell cd IHaskell pip3 install -r requirements.txt stack install --fast ihaskell install --stack ​ jupyter labextension install jupyterlab-ihaskell # did not work ​ stack exec jupyter -- notebook

I haven't actually used IHaskell, however, the png file is presumably created in whatever the working directory is when the script is running. The IHaskell wiki says:

Sounds like you want ghcid. You can use it run tests on a successful build, and it will watch files in your project and quick-rebuild when there are changes. There shouldn't be any need to modify your Cabal files or test dependencies.

In addition, for Haskell, I usually have ghcid running, which likewise re-runs on every file change, but gives faster feedback about any type errors than the full compiler, and also is configured to evaluate

Have you looked into ghcid? https://github.com/ndmitchell/ghcid

VS Code + Haskell extension is usually best, but ghcid is an alternative which is much simpler, easier to set up, less pretty and powerful but still pretty easy and effective to use. Here's a workflow:

In general, though, I recommend just looking at the cabal files for various libraries and executables. Something like ghcid is good, since it contains a library, an executable, and a test suite.

you should also checkout the ghci vim plugin https://github.com/ndmitchell/ghcid/tree/master/plugins/nvim

I just went through the same thing. I settled on using stack and ghcid. All it does is recompile on any change to source code so you at least get lightning fast feedback. Both stack and ghcid have been easy to install and use so far.

Have you tried out ghcid? It basically just runs ghci on your program every time you save, and gives an updated list of errors and warnings. Not interactive in the sense that you don't manually test your functions with it, but like 95% of debugging in Haskell is just fixing errors at compilation time. I find it to be a very nice developer experience. Just need a text editor and a terminal with ghcid open and you get immediate feedback as you program.

https://github.com/ndmitchell/ghcid