Optimizing check value-CodePudding

Is there any way to optimize this code so it can be shorter?

if user_input[0] == "f" or user_input[0:2] == "mu" or user_input[0:2] == "he" or user_input[-1] == "a":

I thought about using a tuple

inputcheck = ('f', 'mu', 'he', 'a')

but then would run into problems when trying to actually check the different options

if user_input == inputcheck #This would of course not work
if user_input[0] == inputcheck #This may work, but 'a' needs to be checked at -1 index of string not at the start

CodePudding user response：

A way to shorten it would be:

if user_input[0] == "f" or user_input[0:2] in ["mu", "he"] or user_input[-1] == "a":

the in allows checking of the list values

CodePudding user response：

If you don't want to use regex and all you want to check is prefixes and suffixes, you can use str.startswith and str.endswith, e.g.:

if user_input.startswith("mu")...

This way, you don't have to match the substring range to the length of the prefix.

A common way to test if a predicate is true for any of a list of values is using python's builtin any function in conjunction with a generator expression:

if any(user_input.startswith(prefix) for prefix in ["f", "mu", "he"])...

If you need some functionality more than once (as you mentioned in a comment), you can extract it into a function, e.g.:

PREFIXES = ("f", "mu", "he")
SUFFIXES = ("a",)

def check_user_input(user_input: str) -> bool:
    return any(user_input.startswith(prefix) for prefix in PREFIXES) or any(
        user_input.endswith(suffix) for suffix in SUFFIXES
    )

CodePudding user response：

Well, a (dirty) solution may be using regular expressions,

import re

user_input = input()

if re.search(r"^f|^mu|^ha|a$",user_input):
    print("works!!")