On Wed, Dec 17, 2003 at 09:19:33AM -0500, Derek Atkins wrote: > Lionel Elie Mamane <[EMAIL PROTECTED]> writes:
>> I would think that in principle having two schedulers in one program
>> is wasteful and less maintainable than having one.
> Well, it very much depends on your definition of "scheduler".. It's
> not that hard to write code that does, effectively:
> for (i = list; i; i=i->next) {
> foo = i->data;
> if (need_to_run_p (foo))
> run(foo);
> }
Well, here, all the date / repeat intelligence is in
"need_to_run_p". That's the part I wouldn't think intelligent to
duplicate, and it is the essence of the scheduler.
>>> Unfortunately you can't just make the SX engine call a "make
>>> invoice" function
>>> first, it would introduce a dependency loop in the code,
>> ? I guess I'll understand this remark when I'll look at the
>> details.
> Basically the business code is all compiled after the engine code,
> and the business code depends on the engine. If you add a
> dependency a dependency in the other direction you now have a
> dependency loop.
Nope, because the engine would depend only on the prototype of the
"make invoice" function, not on its precise definition /
implementation. The engine would #include the right business/foo.h
file, and that's it.
Try this:
-------- A.cpp -----------------
#include <iostream>
#include "local.hpp"
using namespace std;
int main(int argc, char* argv[]) {
cout << "The result is " << a(5) << endl;
}
int a(int n) {
if ( n > 1024 || n <= 0 )
return n;
else
return b(2*n);
}
-------- B.cpp -----------------
#include "local.hpp"
int b(int n) {
return a(n-1);
}
-------- local.hpp -----------------
int a(int n);
int b(int n);
-------------------------
The same dependency loop between A.cpp and B.cpp, eh? This compiles
like this:
g++ -Wall -c -o A.o A.cpp
g++ -Wall -c -o B.o B.cpp
g++ A.o B.o
and also this way:
g++ -Wall -c -o B.o B.cpp
g++ -Wall -c -o A.o A.cpp
g++ A.o B.o
Or maybe I misunderstood your remark.
This discussion is a bit theoretical anyway, as the "no business code
in the engine" condition forbids it.
--
Lionel
signature.asc
Description: Digital signature
_______________________________________________ gnucash-devel mailing list [EMAIL PROTECTED] http://www.gnucash.org/cgi-bin/mailman/listinfo/gnucash-devel
