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Wisp: Small-but-featureful embeddable Lisp interpreter written in Haskell

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Re: Wisp: Small-but-featureful embeddable Lisp interpreter written in Haskell

#5

Post by tel » 

    > wisp lives in the ST (optionally IO) monad. separate 
    > interpreters with completely segregated environments can be 
    > run concurrently. wisp has a few IO facilities, but they're 
    > completely sandboxed and can't accidentally affect the host 
    > program or environment.
This is wonderful. There's already an embedded R5RS Scheme for Haskell (http://hackage.haskell.org/package/husk-scheme) but it runs everything in the IO monad. That makes it fairly annoying for sandboxed embeddings.

Re: Wisp: Small-but-featureful embeddable Lisp interpreter written in Haskell

#6

Post by pygy_ »

sillysaurus2 wrote: post #2

I pine for a Lisp with the embeddable ease of Lua.

It could be trivially implemented in Lua as a pre-processor. Lua has lambdas, higher level functions, lexical scope and tail call elimination.

The main problem is that it doesn't have a ternary operator, making conditional expression problematic to represent (you have to wrap an if statement in a lambda called on the fly).

For something more fully featured, see [0], it is written in MoonScript (which itself compiles to Lua), and the parser depends on LPeg, but writing a S-expression parser is rather easy.

Edit: There's also lcl [1], which is implemented in C. Written by lhf, one of the Lua authors. From the test files, it looks very basic.

--

[0] https://github.com/leafo/moonlisp/tree/master/lisp

[1] http://www.drdobbs.com/open-source/lua-an-extensible-embedde...

Re: Wisp: Small-but-featureful embeddable Lisp interpreter written in Haskell

#8

Post by yoklov »

wcummings wrote: post #3
sillysaurus2 wrote: post #2

I pine for a Lisp with the embeddable ease of Lua.

Guile? http://www.gnu.org/software/guile/

Unfortunately, Guile is both larger, and less portable than Lua. It's also licensed under the LGPL, which is harder (or impossible) to use in some environments than Lua's MIT-like license.

Re: Wisp: Small-but-featureful embeddable Lisp interpreter written in Haskell

#9

Post by yoklov »

sillysaurus2 wrote: post #2

I pine for a Lisp with the embeddable ease of Lua.

ChibiScheme (https://code.google.com/p/chibi-scheme/) tries to be that. I've considered using it but have avoided it due to its relative newness and a few portability issues.
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