运算符只是用|=
联合运算的结果更新您的原始字典。该|
运算符返回一个新字典,它是两个字典的并集。假设我们有两组
a = {'hello', 'world', 'abc', 'def'}
b = {'abc', 'ghi', 'jkl'}
该操作a |= b
与列表的操作a = a | b
方式a += b
非常相似a = a + b
。
a = {'hello', 'world', 'abc', 'def'}
al = list(a)
b = {'abc', 'ghi', 'jkl'}
bl = list(b)
print("Before: ", hex(id(a)), a)
a = a | b
print("After: ", hex(id(a)), a)
# Output:
# Before: 0x1aa0186f128 {'world', 'def', 'abc', 'hello'}
# After: 0x1aa0186f828 {'world', 'ghi', 'hello', 'jkl', 'def', 'abc'}
print("Before: ", hex(id(al)), al)
al = al + bl
print("After: ", hex(id(al)), al)
# Output:
# Before: 0x1aa0187a248 ['world', 'def', 'abc', 'hello']
# After: 0x1aa0366bdc8 ['world', 'def', 'abc', 'hello', 'jkl', 'abc', 'ghi']
显然,a
现在是在内存中不同位置的新集合。
a = {'hello', 'world', 'abc', 'def'}
al = list(a)
b = {'abc', 'ghi', 'jkl'}
bl = list(b)
print("Before", hex(id(a)), a)
a |= b
print("After", hex(id(a)), a)
# Output:
# Before 0x1aa0186f128 {'world', 'def', 'abc', 'hello'}
# After 0x1aa0186f128 {'world', 'ghi', 'hello', 'jkl', 'def', 'abc'}
print("Before", hex(id(al)), al)
al += bl
print("After", hex(id(al)), al)
# Output:
# Before 0x1aa03646888 ['world', 'def', 'abc', 'hello']
# After 0x1aa03646888 ['world', 'def', 'abc', 'hello', 'jkl', 'abc', 'ghi']
在这种情况下,a
仍然是旧集在内存中的同一位置,但其内容已更新。