Bill Baxter wrote:
On Tue, Nov 17, 2009 at 4:17 AM, Don <nos...@nospam.com> wrote:
Bill Baxter wrote:
On Tue, Nov 17, 2009 at 2:07 AM, Don <nos...@nospam.com> wrote:
Travis Boucher wrote:
I've been playing with string mixins, and they are very powerful.
One thing I can't figure out is what exactly can and cannot be evaluated
at compile time.
For example:
----
char[] myFunc1() {
return "int a = 1;";
}
char[] myFunc2() {
char[] myFunc3() {
return "int b = 2;";
}
return myFunc3();
}
void main() {
mixin(myFunc1());
mixin(myFunc2());
}
----
myFunc1() can be used as a string mixin.
myFunc2() can't be.
I think you're using an old version of DMD. It's been working since
DMD1.047. Please upgrade to the latest version, you'll find it a lot less
frustrating.
The bottom of "function.html" in the spec gives the rules.
Though it says nested functions aren't supported, but they are.
Ah, forgot about that list. Good point.
But still Travis should know that the list is not exhaustive.
For instance the other day I found that this didn't work for some reason:
while(i < a - b) { ... }
Instead I had to do
int limit = a-b;
while(i < limit) { ... }
I can't reproduce it. Do you have a complete test case?
Doh! Now I can't either. Maybe it was just a typo that I didn't notice.
How about C functions? Any chance those'll ever work? Particularly C
stdlib functions. They're one of the major things I'm finding
prevents std.string functions from being used CTFE.
I don't think it could ever work. CTFE needs to have the source available.
If we really needed to, a few C stdlib functions could be made into CTFE
intrinsics. But in general, no.
Some form of if(__ctfe) will happen, though.
