patternpythonCritical
Replacements for switch statement in Python?
Viewed 0 times
pythonswitchforstatementreplacements
Problem
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
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?Solution
Python 3.10 (2021) introduced the
The
Documentation:
If you need to support Python ≤ 3.9, use a dictionary instead:
match-case statement, which provides a first-class implementation of a "switch" for Python. For example:def f(x):
match x:
case 'a':
return 1
case 'b':
return 2
case _:
return 0 # 0 is the default case if x is not foundThe
match-case statement is considerably more powerful than this simple example.Documentation:
matchstatements (under the "More Control Flow Tools" page)
- The
matchstatement (under "Compound statements" page)
- PEP 634 – Structural Pattern Matching: Specification
- PEP 636 – Structural Pattern Matching: Tutorial
If you need to support Python ≤ 3.9, use a dictionary instead:
def f(x):
return {
'a': 1,
'b': 2,
}.get(x, 0) # default caseCode Snippets
def f(x):
match x:
case 'a':
return 1
case 'b':
return 2
case _:
return 0 # 0 is the default case if x is not founddef f(x):
return {
'a': 1,
'b': 2,
}.get(x, 0) # default caseContext
Stack Overflow Q#60208, score: 2244
Revisions (0)
No revisions yet.