Kurt Stephens

The source for LL is available at http://github.com/kstephens/ll/tree/master.

Also located there are the slides from my June 2008 talk at the Chicago Lisp Users Group on the design of the LL object-oriented Scheme interpreter:

http://github.com/kstephens/ll/tree/master%2Fsrc%2Fll%2Fdoc%2Fll_system_...

Performance of running the following Scheme code:

(define (tak x y z)
  (if (not (< y x))
      z
      (tak (tak (- x 1) y z)
           (tak (- y 1) z x)
           (tak (- z 1) x y))))

Results:

(tak 18 12 6) (tak 30 15 9) 
(tak 33 15 9) (tak 40 15 9)

ikarus			 0.25 sec
chicken		 1.41 sec (precompiled)
oaklisp		 2.63 sec
mzscheme	    	 2.65 sec
scheme-r5rs	 	 5.89 sec
guile			 7.91 sec
larceny     		10.35 sec
LL  			12.93 sec

Ikarus is burning up; LL needs some heat. :)

• http://www2.lib.uchicago.edu/~keith/crisis/benchmarks/tak/

Download: http://github.com/kstephens/ll/tree/master

LL is:

An embeddable pure, class-based, object Lisp system C library with multiple inheritance and mix-in support based on ideas from Scheme, Oaklisp and Dylan. Clean namespace and proper tail calls in C.

Version 0.15:

• Adds a method lookup cache at all call sites, including primitive C code, reduces full method lookups by over 80%.
• Relies on Bohem GC 7.0 (included).
• Passes R4RS tests.
• Improved bytecode compiler and constant folding on non-side-effecting methods.
• Compiles with GCC 4.1.3.

• call/cc is partially supported.