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Replacements for switch statement in Python?

I want to write a function in Python that returns different fixed values based on the value of an input index.

In other languages I would use a switch or case statement, but Python does not appear to have a switch statement. What are the recommended Python solutions in this scenario?

Answer*

Solution to run functions:

result = {
        'case1':     foo1, 
        'case2':     foo2,
        'case3':     foo3,
    }.get(option)(parameters_optional)

where foo1(), foo2() and foo3() are functions

**Example 1** (with parameters):

option = number['type']
    result = {
        'number':     value_of_int,  # result = value_of_int(number['value'])
        'text':       value_of_text, # result = value_of_text(number['value'])
        'binary':     value_of_bin,  # result = value_of_bin(number['value'])
    }.get(option)(value['value'])

**Example 2** (no parameters):

option = number['type']
    result = {
        'number':     func_for_number, # result = func_for_number()
        'text':       func_for_text,   # result = func_for_text()
        'binary':     func_for_bin,    # result = func_for_bin()
    }.get(option)()

**Example 4** (only values):

option = number['type']
    result = {
        'number':    lambda: 10,       # result = 10
        'text':      lambda: 'ten',    # result = 'ten'
        'binary':    lambda: 0b101111, # result = 47
    }.get(option)()

Edit Summary*

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2

Yes, for example if your variable option=="case2" your result=foo2()
– Alejandro Quintanar
Commented Feb 20, 2018 at 21:27
and so and so forth.
– Alejandro Quintanar
Commented Feb 20, 2018 at 21:41
Yes, I understand the purpose. But my concern is that if you only want foo2(), the foo1(), foo3(), and default() functions are all also going to run, meaning things could take a long time
– Brian Underwood
Commented Feb 21, 2018 at 17:57
2

omit the () inside the dictionary. use get(option)(). problem solved.
– timgeb
Commented Apr 10, 2018 at 6:00
1

Excellent the use of () is a grate solution, I made a gist to test it gist.github.com/aquintanar/01e9920d8341c5c6252d507669758fe5
– Alejandro Quintanar
Commented Apr 17, 2018 at 5:13

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Replacements for switch statement in Python?

Answer*