binaryen VS hint

I've encountered a building problem when using asterius to compile a multi-packages cabal project, the detail could be found here, any suggestions?

ghcjs is the way to go for you, and soon it might be asterius. i do not know how hard it is to set ghcjs up without a framework. but frameworks like obelisk (based on reflex-dom), shpadoinkle, and miso automate that for. i personally like obelisk for its functional reactive programming but it can get awkward and get in your way. so if gui programming is just a means to the end of this one small application and you are not really interested in it nor functional reactive programming, shpadoinkle or miso might suit you better. miso implements the elm architecture (also "TEA", "functional model view controller") and shpadoinkle implements something directly equivalent to the elm architecture. but shpadoinkle achieves more composable widgets by minimalizing the elm architecture. so i recommend shpadoinkle for its better concept although miso is more mature.

Also, hint uses unsafeCoerce, and thus implicitly relies on an assumption about how values are represented at runtime. Namely, if a program P is interpreting an expression E of type A, hint assumes that the value of type A produced by the ghc interpreter has the same representation as the values of type A which are manipulated by program P. This is not guaranteed to be the case, since P has been compiled by the compiler portion of ghc while E has been evaluated by the interpreter portion of ghc. This means the ghc devs had to carefully craft their compiler and interpreters to match. When targetting the browser, a Haskell-to-js or Haskell-to-wasm compiler such as Asterius modifies ghc's code-generator so it produces js or wasm code. You would thus also need to tweak the interpreter so that it produces js or wasm values which match what the modified code-generator outputs. Or you could restrict yourself to the hint's less expressive eval :: String -> String API.

We found a post where someone had a similar issue (here), but the fix in that issue doesn't help: using `ar` from `binutils` causes link errors like this instead:

https://github.com/tweag/asterius/issues/851 (asterius has a demo, but no source, and I -assume no lua filter support)

All modern ones support Haskell: https://github.com/tweag/asterius

Another option is Asterius. I'm not familiar with the current state, and it's not had active development for about 3 months now, either, so it may be in the same boat? But I think the big disadvantage of Asterius is that there's just a lot less usage, and therefore a lot less testing with the whole Haskell ecosystem, versus GHCJS which has been a fixture for a while and where loads of people have thought about compatibility for years.

Check out asterius

I've played around with Haskell via the Asteruis project : https://github.com/tweag/asterius

Also emscripten of course, for C/C++.

Mueval is based on hint, which is in turn based on the ghc library.

Yeah, that project is pretty much at the bottom of my list, unfortunately. My top projects these days are mgmt, klister, recursion-schemes, and hint... And that's already too much!

You can try using hint (instead of ghci) though I'm not sure it has the breakpoint functionality.

Have you tried hint?

with haskell.nix, well, you've found the github issue, you need to put the apecs package in the right nix incantation.

But the use case for that is for using a Haskell program A to catch errors in that same Haskell program A. For your use case, using a Haskell program A to automatically grade a Haskell program B, I recommend using the hint library instead, as it allows you to load code from external source files, run tests on them, and manipulate the error messages produced by ghc. (full disclosure: I am the maintainer of that library)

I am thinking of giving hint the ability to evaluate TemplateHaskell expressions. It would indeed be quite difficult to write an interpreter for all of Haskell, so my plan is to use the Exp's Show instance to produce a program which constructs and then splices that Exp, e.g. $(pure (InfixE (Just (LitE (IntegerL 1))) (VarE GHC.Num.+) (Just (LitE (IntegerL 1))))) is a Haskell expression which is equivalent to 1 + 1, so I should be able to ask hint to evaluate that to get 2 without having to write my own Haskell interpreter.

Yes please! Right now all of my open-source projects (most notably hint and recursion-schemes) are about to drop into barely-updated mode, and while I knew this would happen and have been working towards finding co-maintainers, I am now realizing that it wasn't enough. I think such a website would definitely have helped, and I am hoping that once it launches, I'll be able to use it to find some co-maintainers to tide over my projects until I become available again.

hint's API takes a string, not an AST (I plan to fix this). Internally, hint delegates to the ghc library, which does expose a parser which you can use if you want. hint exists to provide a friendlier API than the ghc library for interpreting Haskell code, but it does not expose a friendlier API for parsing Haskell code.