Simplify README a little. #11

README.md

@@ -131,27 +131,11 @@ For function names which are valid in Scheme but not in Python (such
 as `+`), you'll need to use `register_fn` rather than `scheme_fn`.
 
 At the current time, any builtin function (but not special forms) can
-be overridden using this mechanism:
-
- def strange_plus(args):
-  # addition!
-  if all(typeof(arg) in ['float', 'int']
-  for arg in args):
-  return int_(sum(value(arg) for arg in args))
-  # concatenation!
-  elif all(typeof(arg) == 'list' for arg in args):
-  ret = []
-  for arg in args:
-  ret += value(arg)
-  return list_(ret)
-  # uhhhh... everything else!
-  else:
-  return atom("aStrangerThing")
-
- # warning! Change to built-in function:
- register_fn('+', strange_plus)
-
-Once your Python functions have been registered, your code should then
+be overridden using this mechanism. There's [an example of
+this](https://github.com/eigenhombre/smallscheme/blob/master/smallscheme/test_interop.py#L22)
+in the tests.
+
+Once your Python functions have been registered, your code can then
 execute Scheme expressions, either by executing one or more Scheme
 source files, or by launching a REPL for the user: