> In reply to Bill: ABC (Python's most direct predecessor and influence)
> has quite a nifty global static typechecking algorithm, deriving the
> types of variables (and arguments, etc.) from the use that is made of
> them.
Yes, if the Python compiler could do something like that, even if weaker
(which I don't mind -- stronger checks could be done at run-time, if
wanted), that would allow for the implementation of the levels 2 and 3
of my scheme.
But what was its usefulness in ABC? Seems to me that defining the type
of a variable by the use made of it is overly flexible. (Guess I'll
have to dig out my 4 Dfl (florins?) and find out :-).
Bill