Multiple if-statements with overwriting lists

Question

I currently have the following piece of code in place that attempts to find matches within a list, based on a priority system:

possible_combinations = ["ABC", "AB", "A", "D"]
if len(possible_combinations) >= 1:
 chosen_combination = [comb for comb in possible_combinations if ("A" in comb) and ("C" in comb)]
 if (len(chosen_combination) == 0):
 chosen_combination = [comb for comb in possible_combinations if ("A" in comb)]
 if (len(chosen_combination) == 0):
 chosen_combination = [comb for comb in possible_combinations if ("C" in comb)]
 if (len(chosen_combination) == 0):
 raise ValueError(f"No match found.")
 
print(chosen_combination)
['ABC']

Is there any way I could refactor this code to get rid of these if-statements, and thereby make my code look nicer?

• hjpotter92: perhaps explain why/what, there might be completely different way to solve the problem

Answer 1

You could do something like this:

possible_combinations = ["ABC", "AB", "A", "D"]
combs = [("A","C"),("A",),("C",)]
for comb in combs:
 chosen_comb = [x for x in possible_combinations if all([y in x for y in comb])]
 if len(chosen_comb) > 0:
 break
print(chosen_comb)
 

• Reinderien: Are you sure that this: ("A","C"),("A"),("C") is your intent? The first parens make a tuple, and the second and third do not.
• Tom Gebel: It doesn't really matter here, but you are right. What I meant was [("A","C"),("A",),("C",)]. I corrected it.
• Menno Van Dijk: Looks quite nice. Thx!