This commit is a fairly large refactor, mainly because it unified the
two different ways that existed to represent references.
Now Reference values are also a kind of value.
It also implements a printer for values/references instead of copying
the implementation everywhere.
This allows multiply different kinds of interpreters to be used by the
runtime; currently a BytecodeInterpreter and a
DebuggerBytecodeInterpreter is provided.
This will simply "link" any given module instances and produce a list of
external values that can be used to instantiate a module.
Note that this is extremely basic and cannot resolve circular
dependencies, and depends on the instance order.
Managing the instantiated modules becomes a pain if they're on the
stack, since an instantiated module will eventually reference itself.
To make using this simpler, just avoid copying the instance.
This fixes a FIXME and will allow linking only select modules together,
instead of linking every instantiated module into a big mess of exported
entities :P
Previously, this was parsing only one kind because I mistakenly assumed
that they all had the same shape, now it can parse two kinds, and will
return NotImplemented for the rest.
This adds very basic support for module instantiation/allocation, as
well as a stub for an interpreter (and executions APIs).
The 'wasm' utility is further expanded to instantiate, and attempt
executing the first non-imported function in the module.
Note that as the execution is a stub, the expected result is a zero.
Regardless, this will allow future commits to implement the JS
WebAssembly API. :^)
