[Aldor-l] [open-axiom-devel] generators

[Ralf Hemmecke]

> Just curious: can something of type Generator(Something) ever be a domain?
> (Probably yes...)

 >aldor -fx -laldor aaa.as
 >aaa
MachineInteger
123

---BEGIN aaa.as
#include "aldor"
#include "aldorio"

CAT ==> OutputType with {integer: Literal -> %}
g(): Generator(CAT) == generate {
	yield MachineInteger;
--	yield Integer;
}

foo(D: CAT): () == {
	import from D, TextWriter, String, Character;
	stdout << name(D)$Trace << newline;
	stdout << (123 at D) << newline;
}

for D in g() repeat foo(D);
---END aaa.as

But don't remove the -- before "yield Integer", because then the 
compiler tells you... :-(

"aaa.as", line 5: g(): Generator(CAT) == generate {
                   ................................^
[L5 C33] #1 (Fatal Error) Compiler bug: no exit list for terrorSequence 
(ooops).

Since in Aldor domains are first class, it should be possible to return 
them by a generator. (Compare to lists of domains.)

However, your question asks whether g is a domain if

   g: Generator(Something)

and I would tend to say that this is not a domain. Why? Well, 
"Generator(Something)" should be a category then, right? But if you look 
int sal_gener.as you clearly see that Generator(T) is a domain.

Ralf