from abc import ABC, abstractmethod
from debug_log import p
class AbstractService(ABC):
# abstractmethodには引数がない
@abstractmethod
def test(self) -> int:
pass
class ImplService(AbstractService):
# 具象methodには引数がある
def test(self, a: int, b: int) -> int:
return a + b
def print_method(service: AbstractService) -> int:
return service.test(a=1, b=2)
service = ImplService()
test_value = print_method(service=service)
p(test_value)
- https://docs.python.org/ja/3/reference/datamodel.html#object.__hash__
"""
class Item:
def __init__(self, value: int):
self.value = value
item_1 = Item(1)
item_2 = Item(1)
# valueが同じでも違うオブジェクトとして判定される（これは当たり前）
is_same_item = item_1 == item_2
p(is_same_item) # False
item_set = {item_1}
p(item_set)
# 同じオブジェクトは追加できない
item_set.add(item_1)
p(item_set)
# 違うオブジェクトなので追加できる
item_set.add(item_2)
p(item_set)
from dataclasses import dataclass
from enum import Enum, auto
from debug_log import p
# dataclassとenumは共存できない？どちらにせよ複雑になりそうだからあまりよくなさそうだが
@dataclass
class EnumLike(Enum):
EMPTY = auto()
val: int = 0
# instance = EnumLike(1)
enum_like_value = EnumLike.EMPTY
# p(instance)
p(enum_like_value)
from __future__ import annotations
# python3.9時点だと、このimportしないと -> Testの部分で落ちる
from debug_log import p
class Test:
def __init__(self, value: str):
self.value = value
def from_str(self, value: str) -> Test:
return Test(value + '!!!!!!!!!!!!!!!!1')
test = Test('value')
p(test.from_str('this is test'))
from debug_log import p l1 = [1, 2, 3] p(l1) l2 = l1.copy() l2.append(4) p(l2) p(l1) l3 = l1.copy() + [5] p(l3) p(l1) l4 = l1 + [5] p(l4) p(l1) """ l1 : [1, 2, 3] l2 : [1, 2, 3, 4] l1 : [1, 2, 3] l3 : [1, 2, 3, 5] l1 : [1, 2, 3] l4 : [1, 2, 3, 5] l1 : [1, 2, 3] """
from debug_log import p
class First:
def __init__(self, value: int):
self.value = value
class Second:
def __init__(self, value: First):
self.value = value
# 正しい順序
first = First(1)
p(first)
second = Second(first)
p(second)
class Third:
def __init__(self, value: Fourth):
self.value = value
class Fourth:
def __init__(self, value: int):
self.value = value
# 実行順序逆にしないと通らない
fourth = Fourth(1)
p(fourth)
third = Third(fourth)
p(third)
from debug_log import p
class Cover:
def __init__(self, value: int):
self.value = value
def __repr__(self):
return f'Cover({self.value})'
l = [1, 2, 3]
mapped_l = list(map(Cover, l))
p(mapped_l)
## multi paramater
class Cover2:
def __init__(self, value: int, value2: str):
self.value = value
self.value2 = value2
def __repr__(self):
return f'Cover2({self.value}, {self.value2})'
l2 = [1, 2, 3]
# book2 = Book(book_dict)
# p(book2)
print('--------- fronze=True ----------')
# frozen=Trueの場合のインスタンスの同一性の検証
@dataclass(frozen=True)
class Desk:
height: int
width: int
desk1 = Desk(50, 100)
desk2 = Desk(50, 100)
is_same_desk = desk1 == desk2
# eqはデフォルトでTrueなので、Trueになるはず
p(is_same_desk)
desk_set = {desk1}
p(desk_set)
# frozen=Trueにすることで__hash__が実装されるはず
desk_set.add(desk2)
# 値の同一性で検証されれば追加はできないはず
p(desk_set)