Posted by N V Krishna on February 13, 2004 at 23:01:19:
In Reply to: P3 Questions posted by Steve on February 12, 2004 at 18:59:16:
: The grammar for P3 allows more then one argument to lambda expressions.
: How is that type represented? (t1, t2, t3) -> t4 ?
Just omit the comma's:
(t1 t2 t3) -> t4
: The homework description says: "types are generated from the grammar: t
: ::= t -> t | int | boolean | a where a ranges over a set of type
: variables" Does this mean that if we end up with a completely generic
: type, we should call it a, b, c, ... ?
There is no preferred symbol. Use any identifier of your choice.
: What about ()'s in the result? I presume you want the minimum that will make the expression correct ?
Any number of extra paranthesis is not a problem.
: What is the type of (if x #t 5) ?
Program does not type check.
: What is the type of (set! x 5) ? (my scheme interrpreter returns undefined)
int
Warm regards,
Krishna.