Greetings:
This is a very simple lisp interpreter I've been developing over the
past week or so. So far it does a very good job of parsing input (using
a flex and bison generated parser) and building the AST. The AST
evaluator looks to me like it's working quite nicely, but I still feel
like my tests are lacking and some of the decisions in that code
(particularly in lithp_eval) seem a little hackish. Macro support is
working beautifully... I've encountered no troubles so far. A reasonable
number of primitive functions are included with the interpreter (cons,
car, cdr, lambda, macro, set, add, mult, quote, cond, equals, seq) and
this set seems sufficient for building a good deal of the remaining
language functionality (for, while, if/else, switch). I've built defun,
defmacro, and map (included with bootstrap.l) as interpreted functions
and these are enabled by the interpreter before any other code is
executed. A few other non-standard test functions are included in
bootstrap.l just for fun and demonstration purposes. test.l and t3.l are
fairly comprehensive demonstrations of the language features today and
lettest.l is a scratch pad I'm using to try to implement some more
language features using only the primitive set I have so far. Note that
the primitive set is completely devoid of I/O primitives... therefore
there is no way to really do I/O in this language. Since this is a toy
language, I don't really care. I'll add them later if I want to for some
reason.
Enjoy. Expect it to crash.
The code is fairly legible. There are comments where I felt it was
appropriate, but I generally ignore that type thing and make my
functions short and my variable names obvious.
If you like it... I'd be interested in hearing that. Email me at
el.wubo@gmail.com
-Brian