value.  This affects TALCompiler.py and TALInterpreter.py, and
  affects the output of the non-local-macro expansion tests.  The
  TALVisitor.py module is *not* yet fixed to do this.

- In order to do this, I had to change the "program code" format for
  the attribute list: the 3rd item of an attribute description tuple,
  if present, now names an action, and the remaining tuple items are
  arguments for that action.  Two actions are recognized: "replace"
  replaces the attribute with the outcome of evaluating the expression
  given by the next tuple  item; "macroHack" replaces the attribute
  name with "use-macro" and its value with the current macro, but
  only if we're inside macro expansion and the attribute name ends in
  ":define-macro".

- The test suite is now error-free for "./runtest.py -c" but shows some
  errors for "./runtest.py".

- Added a primitive debugging flag to the TALInterpreter class.

- Update the README.