Does dmd have SSE intrinsics?

[Michel Fortin]

On 2009-09-22 12:32:25 -0400, Andrei Alexandrescu 
<SeeWebsiteForEmail at erdani.org> said:

> Daniel Keep wrote:
>> P.S. And another thing while I'm at it: why can't we declare void
>> variables?  This is another thing that really complicates generic code.
> 
> How would you use them?

Here's some generic code that would benefit from void as a variable 
type in the D/Objective-C bridge. Basically, it keeps the result of a 
function call, does some cleaning, and returns the result (with value 
conversions if needed). Unfortunately, you need a separate path for 
functions that returns void:

		// Call Objective-C code that may raise an exception here.
		static if (is(R == void)) func(objcArgs);
		else ObjcType!(R) objcResult = func(objcArgs);

		_NSRemoveHandler2(&_localHandler);
		
		// Converting return value.
		static if (is(R == void)) return;
		else return decapsulate!(R)(objcResult);

It could be rewriten in a simpler way if void variables were supported:

		// Call Objective-C code that may raise an exception here.
		ObjcType!(R) objcResult = func(objcArgs);

		_NSRemoveHandler2(&_localHandler);
		
		// Converting return value.
		return decapsulate!(R)(objcResult);

Note that returning a void resulting from a function call already works 
in D. You just can't "store" the result of such functions in a variable.

That said, it's not a big hassle in this case, thanks to static if. 
What suffers most is code readability.

-- 
Michel Fortin
michel.fortin at michelf.com
http://michelf.com/