📜  python 多个项目 in with statment - Python 代码示例

📅  最后修改于: 2022-03-11 14:46:10.845000             🧑  作者: Mango

代码示例1
# It is possible in Python 3 since v3.1 and Python 2.7. The
#    new with syntax supports multiple context managers:
with A() as a, B() as b, C() as c:
    doSomething(a,b,c)
# Unlike the contextlib.nested,
#    this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
# You can also use earlier variables in later definitions:
with A() as a, B(a) as b, C(a, b) as c:
    doSomething(a, c)