I have a list:
foolist = ['123-asd', '234-asd', '345-asd']
I want to find the index of the string that contains '234'. At the moment I have this:
boollist = ['234' in i for i in foolist]
which would produce a list of True and Falses for each index for foolist.
Then to find the index, [print(i) for i,j in enumerate(foolist) if j==True]
This seems abit unecessary, does anyone have a more eloquent method of finding the index of a string in list based on a part of that string
You can use next with a generator expression and split by a specific character to reflect the structure of your strings:
foolist = ['123-asd','234-asd','345-asd']
res = next(i for i, j in enumerate(foolist) if '123' in j.split('-')[0]) # 0
If there can be multiple matches, you can use a list comprehension:
res = [i for i, j in enumerate(foolist) if '123' in j.split('-')[0]] # [0]
For equality, you should use j.split('-')[0]] == '123' as your condition instead.
Note on print within a comprehension
It's good practice to avoid print in a list comprehension, as it will return None. You will notice that, while your terminal will print the indices it finds, you are also building a list of None items with length equal to the number of matches. For all intents, that list has no use.
If you are only interested in printing items, you can use a for loop with a generator expression:
for idx in (i for i, j in enumerate(foolist) if '123' in j.split('-')[0]):
print(idx)
None in a list comprehension, the bad-practice bit is using the list comprehension for side-effects and discarding the result.
[i for i,j in enumerate(foolist) if '234' in j]?