What is the Python equivalent for a case/switch statement?

John Alley picture John Alley · Jul 14, 2012 · Viewed 1.3M times · Source

I'd like to know, is there a Python equivalent for the case statement such as the examples available on VB.net or C#?

Answer

Prashant Kumar picture Prashant Kumar · Jul 14, 2012

While the official docs are happy not to provide switch, I have seen a solution using dictionaries.

For example:

# define the function blocks
def zero():
    print "You typed zero.\n"

def sqr():
    print "n is a perfect square\n"

def even():
    print "n is an even number\n"

def prime():
    print "n is a prime number\n"

# map the inputs to the function blocks
options = {0 : zero,
           1 : sqr,
           4 : sqr,
           9 : sqr,
           2 : even,
           3 : prime,
           5 : prime,
           7 : prime,
}

Then the equivalent switch block is invoked:

options[num]()

This begins to fall apart if you heavily depend on fall through.