The "no gc" crowd

[Adam D. Ruppe]

On Tuesday, 8 October 2013 at 22:53:35 UTC, Walter Bright wrote:
> What you're suggesting is called "interprocedural analysis" and 
> doesn't work in a system with separate compilation (meaning 
> that function bodies are hidden from the compiler).

Eh, that's not a dealbreaker, especially with phobos and druntime 
where the source is always available anyway.

Though, my proposed __traits could perhaps be improved to just 
offer two things:

__traits(getFunctionsCalled, function)

returns a tuple of all functions called. These would ideally be 
in the form of symbols.

__traits(functionBodyAvailable, function)

true if the source was available to the compiler.


And that's it: the rest is done in the library using existing 
language features. Then we can decide in library code if a 
missing attribute is a problem based on if the body was available 
or not.

Note that this isn't specific to the gc: it would provide the 
necessary foundation for all kinds of library extensions in the 
same vein as @safe, with the possibility of automatic inference 
from the prototype + presence of body.