Tree structures

[ArachnidAbby]

Description

Add in new NTree datastructure that makes working with tree datastructures extremely easy.

class ModuleName:
  ...

class Module:
  ...

class ModuleView:
  ...

class Package(NTree[ModuleView, str]):
    """An example of an extension of NTree"""
  ... #impl in full file


imports = Package(
    identifier="base",
    leaves=[
        Module("main", private=True),
        Module("other_mod"),
        Package(
            identifier="lib",
            leaves=[
                Module("math"),
                Module("system"),
                Module("err"),
                Package(
                    identifier="ui",
                    leaves=[
                        Module("application"),
                        Module("widgets"),
                        Module("internal_stuff", private=True),
                        Package(
                            identifier="bindings",
                            leaves=[
                                Module("application", private=True),
                                Module("widgets", private=True),
                            ],
                        ),
                    ],
                ),
            ],
        ),
    ],
)

# NTree supports:
#  - intersection via `&` operator
#  - combining via `|` op
#  - custom leaf initialization (useful for those ModuleView classes)
#  - Two kinds of indexing (NTree indexing and Leaf node indexing) via the index operator
#  - Comparison via `==`
#  - arbitrary tree/leaf matching (via common interface/protocol)
#  - Fully supported type annotation that work fantastically (avoiding bare type unions and instead using overloads to provide more accurate typing when calling a function or using an operator)