David Van Horn scripsit: > I keep hearing this stuff about Scheme being a lexically scoped > language. I don't buy it (or at least, I think it's more subtle than > one might believe). > > What is the definition of lexical scope being employed here?
That the meaning of an identifier used in a given construct such as define or define-syntax is determined solely by what identifiers are bound at the point of definition, and *not* by any bindings in effect at the point of use. Lexical scoping of variables is pretty much accepted, at least as the default, in all current programming languages except Emacs Lisp. Common Lisp and Perl provide indefinitely scoped variables with dynamic extent (slangily called "dynamic scope") as an option. Lexical scoping of macro-time parameters remains a bone of contention between the Common Lisp and Scheme communities. -- If you understand, John Cowan things are just as they are; http://www.ccil.org/~cowan if you do not understand, [email protected] things are just as they are. _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
