[ANN] Chuck type inferencer
cputney at wiresong.ca
Tue Jun 8 18:23:16 UTC 2004
On Jun 8, 2004, at 11:38 AM, Avi Bryant wrote:
> On Jun 8, 2004, at 9:15 AM, Colin Putney wrote:
>> The simplest, cleanest, most OO, way of executing code would be to
>> have the VM execute an AST directly.
> I'm not convinced this is true: bytecode is a much simpler interface
> between the image and the VM than an executable AST would be. I also
> wouldn't want the VM to depend on even the abstract syntax of
> Smalltalk, since this would make it much more difficult to experiment
> with targeting other languages to the Squeak VM - they'd have to be
> translated to a Smalltalk AST rather than compiled to a neutral
> bytecode. My "Sorrow" concatenative compiler, for example, would have
> been much harder to write.
> The stack machine is a valuable abstraction, I don't think we want to
> throw it away.
Yeah, that probably should have read "way of executing *Smalltalk*
I agree that the stack machine is a valuable abstraction, and bytecode
forms a simple and general interface between the image and VM, which
also has value.
However, it's not clear to me that an interpreter for an AST is any
more complicated than a bytecode interpreter. And looking strictly at
the image, I do think my assertion is correct - executable ASTs are
simpler and more object oriented. So I'll take your comment to mean
that there other considerations than simplicity in the image -
decoupling the image from the VM is valuable as well. Agreed.
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