Add Integer and Float InterenceVariable

In order to properly handle all integer types and infer we must follow HM
algorithm. This means when we unify every type in the resolver this should
keep a chain of HirId of references such that when/if the type is resolved
it lookup tables can be updated for the Backend to compile to Gimple.

Consider the case:

fn test(x:u32) -> u32 {...}
let a = test(1);

The VarDecl here will have the type let a:<I?> = test<u32>(1<I?>).
Since this integer combines with the parameter x:u32 the type resolver
knows at this point these must be a u32.

let a;
a = 1;
let b:u32 = a;

This is more subtle

let a:<?>
a:<?> = 1<I?>
let b:u32 = a<I?>;

Since the integer inference variable combines with u32 all previous
references can be updated to u32 at this point.

In the basic case of:

let a;
a = 1;

This resolves down to:

let a:<I?>;
a<I?> = 1<I?>

It is not until we complete type-inference we can iterate all the
resolved types and HirIds and default any <I?> to i32 and any <F?> to f32.
Any remaining general inference variable are errors.

0 files changed, 0 insertions, 0 deletions