A simple "meta-circular scheme" interpreter.

* mcs.ss

This is a simplified version of the mcscheme interpreter that has the
following limitations and additions.


  (1) I've added begin, which takes an arbitrary number of arguments,
  evlautes them from left to right and refurns the value of the last
  one.

  (2) lambda only allows one expression in its body.  If you want to
  do more things in the body, use an explicit begin, as in

     (lambda (x) (begin (define y (* x x)) (* y y)))

  (3) define can only assign a variable to a value, i.e., its first
  argument has to be a symbol.  You can define a function using
  lambda, as in:

    (define add1 (lambda (x) (+ x 1))

  (4) There is no set!  The set function can assign variables outside
  of the local environment (e.g., global variables).  You can use
  define to either create a new variable in the local environment or
  to give a local variable a new value.

* mcs_basics.ss

This file is intended to be loaded and evaluated by the mcs
interpreter. It defines some variables and functions that extend mcs
and also demonstrate what it can do.

* mcs_scope.ss

This is the version with a global scheme variable that can switch the
interpreter from static to dynamic scoping.

* session.txt

A session captured with the unix script command that shows mcscheme in
action.