Lisp in 1,200 lines of Dart

This is a Lisp interpreter with macros, backquotation and tail-call optimization. It is written in 1,200 lines of a script in Dart 1.9.

  $ curl -R -O http://www.oki-osk.jp/esc/dart/lisp/lisp-27-04-20.tar.bz2
  $ tar xf lisp-27-04-20.tar.bz2
  $ cd lisp-27-04-20
  $ wc lisp.dart 
      1200    4696   36500 lisp.dart
  $ dart lisp.dart
  > (defmacro aif (test then &rest else)
       `(let ((it ,test))
           (if it ,then ,@else)))
  aif
  > (defun find (x list)   
        (aif (member x list) (car it)))
  find
  > (find 10 '(1 2 3))
  nil
  > (find 2 '(1 2 3))
  2
  > find
  #<closure:2:nil:((#<lambda:1:((cond (#0:0:it (car #0:0:it))))> (member #0:0:x #0:1:list)))>