Is it possible to get at the file and line number of where a function is being called from? For example:

	class A {
		int opIndex(int x) {
			/* do a bunch of checks */
			if (checkFailed)
				throw new RangeError(...);

			/* compute value */
			return value;
		}
	}

I'd like to be able to throw the exception referencing the file/line of the caller, rather than opIndex() itself. Is this possible?


T

-- 
Two wrongs don't make a right; but three rights do make a left...

On Saturday, 3 March 2012 at 01:36:51 UTC, H. S. Teoh wrote:
> 		int opIndex(int x) {

Make that

(int x, string file = __FILE__, int line = __LINE__)

and use file/line in there. The exception consturctors
do this, so you can

throw new Exception("msg", file, line);

and get it passed on.

Le samedi 03 mars 2012 à 02:39 +0100, Adam D. Ruppe a écrit :
> On Saturday, 3 March 2012 at 01:36:51 UTC, H. S. Teoh wrote:
> > 		int opIndex(int x) {
> 
> Make that
> 
> (int x, string file = __FILE__, int line = __LINE__)
> 
> and use file/line in there. The exception consturctors
> do this, so you can
> 
> throw new Exception("msg", file, line);
> 
> and get it passed on.

I think __LINE__ is size_t not int

On 3/3/12, bioinfornatics <bioinfornatics@fedoraproject.org> wrote:
> I think __LINE__ is size_t not int

I'd love to see a 2_147_483_648 line source file! :D

On Saturday, March 03, 2012 13:21:05 bioinfornatics wrote:
> Le samedi 03 mars 2012 à 02:39 +0100, Adam D. Ruppe a écrit :
> > On Saturday, 3 March 2012 at 01:36:51 UTC, H. S. Teoh wrote:
> > > 		int opIndex(int x) {
> > 
> > Make that
> > 
> > (int x, string file = __FILE__, int line = __LINE__)
> > 
> > and use file/line in there. The exception consturctors
> > do this, so you can
> > 
> > throw new Exception("msg", file, line);
> > 
> > and get it passed on.
> 
> I think __LINE__ is size_t not int

Yes, it's size_t.

- Jonathan M Davis

On Sat, Mar 03, 2012 at 03:52:55PM +0100, Andrej Mitrovic wrote:
> On 3/3/12, bioinfornatics <bioinfornatics@fedoraproject.org> wrote:
> > I think __LINE__ is size_t not int
> 
> I'd love to see a 2_147_483_648 line source file! :D

It *could* happen if the source file was auto-generated... and the autogenerator was broken. :P

Of course, with D's templates, CTFE, and compile-time introspection capabilities, I can't imagine when autogeneration would actually be required, but we're talking about hypotheticals here.


T

-- 
Debian GNU/Linux: Cray on your desktop.

On 3/3/12, H. S. Teoh <hsteoh@quickfur.ath.cx> wrote:
> Of course, with D's templates, CTFE, and compile-time introspection capabilities, I can't imagine when autogeneration would actually be required, but we're talking about hypotheticals here.

It can be if you need an OOP D binding to a C/C++ library. E.g. QtD uses an autogenerator, GtkD as well.

On Saturday, March 03, 2012 23:01:38 Andrej Mitrovic wrote:
> On 3/3/12, H. S. Teoh <hsteoh@quickfur.ath.cx> wrote:
> > Of course, with D's templates, CTFE, and compile-time introspection capabilities, I can't imagine when autogeneration would actually be required, but we're talking about hypotheticals here.
> 
> It can be if you need an OOP D binding to a C/C++ library. E.g. QtD uses an autogenerator, GtkD as well.

All it takes is a function passing a size_t to that function rather than letting it use its default value, and you'll get problems on 64-bit systems if you made the line number an int. It really needs to be a size_t, even if you'll never have a value for it which is high enough to need it.

- Jonathan M Davis

Ok, well a quick search shows socket.d:132 needs fixing. Also there's two versioned out enforces in object_.d which use int line = __LINE__. Interestingly, earlier versions of Phobos used int a lot (I guess in pre-64bit compatible D days). I'm also seeing int used in Derelict, pspemu, plot2kill and dwt2.

On Sunday, March 04, 2012 03:38:03 Andrej Mitrovic wrote:
> Ok, well a quick search shows socket.d:132 needs fixing. Also there's two versioned out enforces in object_.d which use int line = __LINE__. Interestingly, earlier versions of Phobos used int a lot (I guess in pre-64bit compatible D days). I'm also seeing int used in Derelict, pspemu, plot2kill and dwt2.

It's a common error to use int where size_t should be used. Using int when dealing with __LINE__ is just one case of that. It didn't start actually causing compilation errors until we go 64-bit dmd though.

- Jonathan M Davis