‘python之switch实现’

from __future__ import division
def (x, y):
    return x + y
def subtract(x, y):
    return x - y
def multiply(x, y):
    return x * y
def divide(x, y):
    return x / y
result = {
    '+': add,
    '-': subtract,
    '*': multiply,
    '/': divide
}
def f(x, op, y):
    print result.get(op)(x, y)
f(4, '+', 9)