This is a "quick and dirty" interpreter for a Scheme-ish language in Haskell, mostly based off of Peter Michaux's article "Scheme From Scratch." It's my way of getting better with Haskell while simultaneously learning about Scheme & Lisp See Prelude.hscm and Test.hscm for usage.

Install & Run

1. install Parseclone
2. download hsscheme source, unzip, and cd into extracted directory
3. $ sudo cabal install (note: the dependency tree is pretty big, because of the view experimental feature -- see below)
4. create /usr/lib/hsscheme/ and move Prelude.hscm there
5. $ hsscheme (for REPL) or $ hsscheme myfile.hscm (to run file)

Developed on Ubuntu and OS X with GHC 6.12.1.

Experimental Feature: View

The function view visualizes data structures using Ubigraph, via vacuum-ubigraph. Usage:

1. install ubigraph (see site)
2. start server: $ ubigraph_server
3. in hsscheme: >> (view [any value])

This uses vacuum to display the Haskell data structures (SchemeObj in Language/Scheme/Model.hs) representing Scheme objects. Try visualizing a non-builtin function (just (view myfunc)) -- it'll visualize the data that is the code for that function. Not very useful, but pretty neat.

TODO

• lambdas (closures)
• tracebacks
• source locations for error messages
• a catch form
• fail gracefully when ubigraph_server isn't running and view is called