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ndmitchell / ghcid

Very low feature GHCi based IDE
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Question about integrating ghcid build as local compiler/dev tool with the vscode extension #307

Open maxild opened 4 years ago

maxild commented 4 years ago

Hi,

The docs for the extension says that ghcid should be a global tool. What if ghcid have been installed with

stack build --copy-compiler-tool ghcid

from inside a stack project. Then

stack exec -- which ghcid

/Users/maxfire/.stack/snapshots/x86_64-osx/cc58f8a7e119ba62c66366b87ed60b09f419a9292a60768cbbcb21d20bfea7f0/8.6.5/bin/hoogle

shows that ghcid is a local tool handled by stack, and have to be executed with

stack exec ghcid -- <args>

Is this setup supported by the vscode extension?

If I have to install it as a global tool with cabal install or stack install, then this guide says that I have to rebuild everytime, I build with a version of GHC that doesn't match the GHC version that build the tool. I guess this is why the local tool is cached in a snapshot per OS and GHC version. I can't really see that a tool like ghcid cannot be used with 2 projects using different GHC versions. Is this really correct?

I have the same question for other tools hoogle, hlint and hindent, and can't see why they cannot be used cross projects compiling with different versions of GHC (maybe linter and pretty-printer are affiliated with the lexer and parser and need to be aligned?).

I am pretty new to Haskell tooling/community, so sorry for asking broad question in GH issue.

ndmitchell commented 4 years ago

Ghcid deliberately works with a wide variety of compilers, so you can compile Ghcid with GHC 8.2, then use it on projects with 8.4, 8.6 and 8.8 without requiring a different build. The information in that guide doesn't talk about ghcid at all, which has different properties. I suggest installing a single global binary. Ditto for Weeder, Hoogle and HLint, which can be used at different versions. I have no idea about hindent.

That said, feel free to follow the instructions in that guide, you just have to change the ghcid.command configuration key to point at a command that runs ghcid - e.g. stack exec ghcid --.

maxild commented 4 years ago

Thanks. I think its the "IDE" (haskell-ide-engine, ghcide) tools that has to be aligned with the compiler versions, right?

I am starting to put "holes" into my haskell code (as in foldr _cons _nil), and GHCI will show type info about the missing hole, and also what is in scope (the bindings). Pretty neat!

But ghcid seem to truncate the output, and with two or more holes I can't read all the output from GHCI on my screen. Is this configurable somehow?

ndmitchell commented 4 years ago

Ghcid shows as many things as it can, but limits it at the height of your console. Make the console bigger and you should see more. In the VS Code extension it should show you everything even if the console isn't big enough.