[Haskell-cafe] More on the random idea

[Neil Mitchell]

HI

> For me, the unfortunate thing is that there seems to be no interpreter
> for Haskell written in Haskell. (Except for GHC, which is *huge*.)

What do you mean by *huge*? Takes up to much memory at runtime?
Requires too long to compile? Has had too many experts spending lots
of time writing it? A large volume of source code isn't a negative,
unless you are expected to do something with it that involves
modifying a large chunk of it.

> We
> have a Haskell parser [which is complex beyond usability]

Which takes a Haskell file and produces an abstract syntax tree
representing Haskell? I'm not sure how that's complex, it does exactly
what it says on the tin - it parses Haskell.

> them find it doesn't implement Haskell precisely. So it looks like I'm
> stuck with present technology - and that essentially means GHC. (Other
> compilers? What other compilers??)

Yhc, Hugs, JHC...

> As far as I know, hs-plugins works by taking an expression, writing it
> to a file, calling GHC to parse it, transform it to Core, optimise it,
> transform it to STG, optimise it, transform it to C--, optimise it,
> transform it to ANSI C, optimise it, pass it to GCC, compile it, link
> it, and *then* using the GHC runtime linker to load the generated object
> code into memory, type-check it, and, finally, execute it.

Are you complaining that this process is too slow? Complaints about
speed should take the form "I expected this to happen in 3 seconds, it
requires 12". You can't have a complaint about it doing clever things
automatically for you, only that the results of those clever things
don't meet your needs.

> Whatever... I'd just like to see an online way to run Haskell, and since
> the Lambdabot webpage still shows no sign of working...

Writing a Haskell interpreter seems like a lot of work, if all you
want is "a few tweaks to lambdabot". Of course, a Haskell interpreter
is something I'd love to see :)

Thanks

Neil