[plt-scheme] What are "and" and "or" ?
Marco Morazan wrote:
> I had students
> complain that they could not pass "and" and "or" around. From a
> padagogical viewpoint it is a little awkward to tell young newcomers
> that "and" and "or" are not primitives.
I tell students while introducing "and" and "or" that they are special
forms, not functions. Without this, I can't explain the short-cutting
semantics. They've already seen the special form "cond", so they
understand. Later on, when we do abstract list functions, I remind them
again that "and" and "or" are special forms, and tell them about
"andmap" and "ormap". It hasn't caused any problems for me in the last
few years. --PR