Haiku, Meet Lua. Lua, Haiku

I've been pretty quiet since I got out of school last week. It's not because I've been too busy to do anything. Quite the contrary. I've had my head down in the trenches, hacking away. About six months ago, I posted a screenshot of CHaikuRun, a test application which interacted with the Haiku API from the C language. I have a new one:

On the outside, not all that different from the other one. Under the hood, though, the two test apps are worlds apart. Here is the source code:


function LuaAppSetupFunction()
    local win = MakeObject("PWindow");
    win.SetProperty("Frame", PRect(100,100,500,400))
    win.SetProperty("Flags", BQuitOnWindowClose)
    win.SetProperty("Title", "LuaGUI")

    local view = MakeObject("PView")
    view.SetProperty("Frame", PRect(0,0,400,300))
    view.SetProperty("BackColor", PColor(224,224,224));
    win.RunMethod("AddChild", {view.id})
   
    local label = MakeObject("PLabel");
    label.SetProperty("Frame", PRect(10, 10, 350, 60))
    label.SetProperty("Text", "Haiku, meet Lua!");
    view.RunMethod("AddChild", {label.id})
end

RunApp("application/x-vnd.dw-LuaGUI", "LuaAppSetupFunction");


That's pretty darn short, if you ask me. A graphical HelloWorld app can be written in 6 lines of code:

function LuaAppSetupFunction()
    local win = MakeObject("PWindow");
    win.SetProperty("Flags", BQuitOnWindowClose)
    win.SetProperty("Title", "Hello Haiku!")
end

RunApp("application/x-vnd.dw-LuaGUI", "LuaAppSetupFunction");


And I thought writing in C++ was easy. Yeesh. That beats everything I've seen under Haiku/BeOS except yab and quite competitive to something like wxPython. Then again, I could argue that this is a lot clearer than yab, but I digress.

The code snippets I've posted above are why I manually wrote Lua bindings instead of using SWIG. I'm not sure that I could have gotten SWIG to generate them in a way which has at least the same ease-of-use as the C++ API. I've still got a *lot* more testing to do and some more objects to implement before I can do a release, but this is definitely some progress and some good news, too. It's officially a good day now. :)

Libcharlemagne and Paladin

Just a quick post before I head off to bed. :) While school has been as busy as typical this year, last week and this week (mostly this) have been spent with many moments coding. The results? Project-wide find and replace -- a long-needed feature -- and major progress on libcharlemagne. Most of this library work has actually been spent on writing Lua bindings for libcharlemagne. It's not there yet, but it's getting there.

Originally I was going to use SWIG to do it, but it's hard to have a nice API in a language using a generic wrapper. Some language features just don't wrap very well. On the up side, I found out just how flat-out easy it is to call C from Lua. It's almost scary how easy it is. Current code in writing is to turn tables into libcharlemagne's generic data container and vice versa. Hopefully it won't be *too* long before I can post the source for a Lua script that uses the GUI and make a testing release. TTFN