Files
hooked-containers/src/hooked_containers/list.py
John Lancaster 8cff84f4e9 mutablesequence
2026-02-21 18:28:40 -06:00

73 lines
1.6 KiB
Python

from collections.abc import Callable, MutableSequence
from dataclasses import dataclass
from enum import Enum, auto
from typing import Generic, TypeVar
T = TypeVar("T")
class ListChange(Enum):
ADD_ITEM = auto()
REMOVE_ITEM = auto()
SET_ITEM = auto()
@dataclass(frozen=True)
class ListChangeEvent(Generic[T]):
index: int
@dataclass(frozen=True)
class AddItemEvent(ListChangeEvent[T]):
item: T
@dataclass(frozen=True)
class SetItemEvent(ListChangeEvent[T]):
item: T
@dataclass(frozen=True)
class RemoveItemEvent(ListChangeEvent[T]):
item: T
class HookedList(Generic[T], MutableSequence[T]):
elements: list[T]
hook: Callable[[ListChangeEvent[T]], None] | None
def __init__(self, *args, hook=None, **kwargs):
self.elements = list(*args, **kwargs)
self.hook = hook
def __repr__(self):
return f"{self.__class__.__name__}({self.elements!r})"
def __iter__(self):
return iter(self.elements)
def __contains__(self, value):
return value in self.elements
def __len__(self):
return len(self.elements)
def __getitem__(self, s):
print("Getting item:", s)
return self.elements[s]
def __setitem__(self, s, value):
self.elements[s] = value
if self.hook:
self.hook(SetItemEvent(index=s, item=value))
def __delitem__(self, s):
del self.elements[s]
if self.hook:
self.hook(RemoveItemEvent(index=s, item=self.elements[s]))
def insert(self, index, value):
self.elements.insert(index, value)
if self.hook:
self.hook(AddItemEvent(index=index, item=value))