AST

`Spec` nodes

Actual definition of one of language's entities:

Types
- Numeric
  - Boolean
  - Signed integer
  - Unsigned integer
  - Floating point
- Function
- Pointer
- Compound
  - Struct
  - Union
Functions
Variables

`Decl` nodes

Instances of spec declaration (assigning a symbol name to language entity spec).

`Value` nodes

Symbols resolve to values.

Specs resolved from symbols through declarations.
Specs defined in place.
Constants