OpenWL/DL - two foundation libraries for building a cross-platform GUI with non-C++ languages

[DanielG]

Well, I have some time on my hands so I guess I'll answer "Why 
not write this in D?"

1) The easiest way to access platform-native stuff is to use 
platform-native tools (Xcode/Objective-C, Visual Studio/C++/COM, 
etc). At a minimum I would have to translate header files, and 
rely on D having perfect Objective-C and COM support, or whatever 
else some future/exotic platform might require. By doing it this 
way, I completely bypass all that extra work, and I can always 
utilize the latest platform SDKs with a few simple clicks. "When 
in Rome..."

2) I intend to support other platforms where D currently doesn't 
exist, which means I would either have to port it myself, or wait 
for somebody else to do it. But this way I can go pretty much 
anywhere that Cairo/Pango can be built (and someday hope to even 
drop the Pango requirement).

3) If I used D, then invariably the GC haters would complain and 
refuse to depend upon my libraries purely on superstitious 
grounds. And if they aren't using them, they certainly aren't 
going to help porting/bugfixing/etc. And I consider it more than 
a little likely the D crowd would reject my work if I wrote it 
all in pure D, on account of being disappointed in whatever 
idiosyncratic API I came up with!

4) D isn't the only language I use, and I want to be able to take 
advantage of these libraries anywhere I happen to go in the 
future. If I did what Qt did, and build everything at 
ground-level in a specific language, then it's no longer 
language-agnostic and I would keep having to reinvent the 
cross-platform wheel every time I want to change languages. Or 
else struggle with trying to create bindings, and we all know how 
that goes (how many Qt bindings have been attempted in non-C++ 
languages, and ultimately abandoned?)

I'm doing this for myself, and while I'm using D for my current 
project (which inspired all this), I won't be here forever. But I 
will probably always need a GUI wherever I go, and I'm doing my 
part to make that available for my future self. I know from 
experience, 20 years ago, that writing a GUI from scratch in a 
single language / for a single platform (or in this case, for a 
platform abstraction) is reasonably realistic for one focused 
individual. And with modern languages and tooling? Heavenly.