D to Javascript converter (a hacked up dmd)

[Adam D. Ruppe]

On Wednesday, 29 February 2012 at 02:42:38 UTC, Piotr Szturmaj 
wrote:
> 44 KB - that's not bad!

It actually gets better: 9kb if you trim the mangled names
down to size (I've written a mangle name trimmer and an
unused function cutter; hello world is about 200 bytes.).


The reason it didn't work before wasn't just dollar, but also
ref params. This was a bit of a pain.. without pointers, how
can I implement this?

After thinking on it for almost an hour, I decided on passing
lambdas instead:

void a(ref b) { b = 10; }

int c = 5;
a(c);
assert(c == 10);


The JS looks like this:

function a(b) { b(10); }
var c = 5;
a(function(set) { if(typeof set != "undefined") c = set; return 
c; });
c == 5 || _d_assert();


My implementation right now is a filthy hack... but std.algorithm
is basically working. assumeSorted's constructor is missing for
some reason, but the algorithm itself actually worked.

(I spent time making class constructors work, but I think I
neglected struct constructors, so probably easy fix.)



But, I think the best thing to do though isn't to port phobos
implementations, but instead port the interface as much as 
possible.

sort can be a wrapper of Array.prototype.sort() from Javascript,
thus letting us leave out the implementation. Odds are the native
method will be faster anyway.


> Some time ago, I was interested in translation to JS, but I 
> rather thought about binary translation, like in 
> http://bellard.org/jslinux/. There's similar "emscripten" 
> project which translates LLVM bytecode to JS:

I've heard of these two, but they seem a lot bigger than
I like.

I want the generated JS to be as small as possible while
still covering a good chunk of D features.