minimal object.d implementation that allows classes

[Adam D. Ruppe]

On Wednesday, 6 December 2017 at 18:32:11 UTC, Luís Marques wrote:
> On Wednesday, 6 December 2017 at 17:52:16 UTC, Eugene Wissner 
> wrote:
>> http://arsdnet.net/dcode/minimal.zip ?
>
> I tried that one, but I was having trouble getting it to work 
> (it seems to have bit rotten), and it does much more than I 
> need, which probably is adding to the work to fix it.

Yeah, minimal.zip is getting a bit old, but most the changes 
should be fairly small - adjusting sizes mainly. I just haven't 
done that for a year or two.

The basic process is compile and link, if something doesn't work, 
copy/paste enough in to make the error go away. Sizes can be 
gotten from real druntime with __traits(classInstanceSize) and 
such, then you put in a dummy buffer to pad to it (remembering 
the vptr and monitor already get tou part of the way there).

minimal.zip does a bit more than the bare minimum, but 
polymorphic classes DO require a fair chunk of code - various 
typeinfo and cast functions, some kind of memory function - and 
some of that code requires other code like struct typeinfo too 
(ugh, but the compiler insists).

minimal.zip also includes exceptions and some startup stuff but 
that's mostly just because such were easy after polymorphism 
worked so I did because I can. Of course, if targetting 
webassembly, you can prolly cut all that out and rely on the 
javascript plumbing instead (i think). Certainly the asm 
functions will need to be cut there.