This project is a small experiment of mine to see how much you can do with lisp on the lowest levels, that is making the interpreter as small as possible and implementing most of Scheme's functionality within the language itself.

So far the interpreter has the following features built-into the interpreter:

• Primitive expressions: integers, floats, strings, builtin functions, pairs
• Special values: nil, inf, nan
• Checking type of the expression:
  • int?
  • flt?
  • nil
  • sym
  • pair
  • func
• Integer functions:
  • Bitwise logic: int-bnot, int-bor, int-band, int-bxor
  • Arithmetic: int-neg, int-add, int-sub, int-mul, int-div, int-rem
  • Comparison: int-les?, int-grt?, int-eq?, int-neq?, int-leq?, int-geq?
• Floating-point functions
  • Conversion to/from integers: flt-from-int, flt-round, flt-trunc, flt-ceil, flt-floor
  • Classification: flt-inf?, flt-nan?, flt-normal?
  • Arithmetic: flt-neg, flt-add, flt-sub, flt-mul, flt-div
  • Comparison: flt-les?, flt-grt?, flt-eq?, flt-neq?, flt-leq?, flt-geq?
• Symbol equality: sym-eq?
• Pair functions:
  • car
  • cdr
  • cons
• I/O:
  • print-ch
  • input-ch
  • print

The booleans are not implemented in this lisp dialect. Similarly to C, integers are used instead. The zero value corresponds to true, and non-zero value to false. The identifiers true, false aren't defined.

To build the project clang required. On windows run via Visual Studio developer's command prompt.

$ git clone https://github.com/flysand7/blisp.git
$ cd blisp
$ bake
$ blisp

This should open up the REPL mode of the interpreter. You can write something simple, like

> (print (int-mul (int-add 5 3) -2))
-16