Python OR运算符和括号

Question

示例1 - 这有效:

def thisorthat():
    var = 2

    if (var == 3 or var == 2):
        print "i see the second value"
    elif (var == 2 or var == 15):
        print "I don't see the second value"

thisorthat()

示例2 - 这不起作用:

def thisorthat():
    var = 2

    if var == (3 or 2):
        print "i see the second value"
    elif var == (2 or 15):
        print "I don't see the second value"

thisorthat() # "I don't see the second value"

有没有办法将变量与"OR"运算符进行比较,而不是在每一行中重复两次变量？

Answer 1

这是一种等效的方式:

if var in [2, 3]:
    ...
elif var in [2, 15]:
    ...

并且您var每个条件只使用一次.

笔记:

• 这不是OR直接使用.
• 将2在第二个状态并没有真正意义.