merits of Lisp vs Python

[greg]

Ken Tilton wrote:

> How does a generic engine that sees only a solution (a 
> list of mathematical expressions and for each the transformations, 
> results, and opnds logged by individual TF functions) build up this 
> environment such that it has named attributes such as signed-value?

How did your macro know that the user's reverse function
needed a signed_value parameter in that particular case?

> Assume that it can examine all those opnds and results looking
> for tagged values such that it then knows the name of those values
> that have been named.

You might be able to handle this using a general method
that searches the tree for a specified tag, e.g.

    env.find_tag("signed_value")

--
Greg