Adding a suffix to both elements in a list and to a variable at the same time

Question

Say I have a list of strings:

myList = ['apple','banana','orange']

and another string saved into a single variable:

myVariable = 'fudge'

I want to add the suffix _df2 to every element in myList, and also to myVariable. Therefore, I want my result to look like this:

>> myList
['apple_df2', 'banana_df2', 'orange_df2']

>> myVariable
'fudge_df2'

Currently I am achieving this with the following code:

myList = [fruit + '_df2' for fruit in myList]
myVariable = myVariable + '_df2'

I am wondering, however, since I am adding the same suffix both times, is there a way to sum these two steps up into one?

There's no way to do it in one step (in one line possibly, but that's not a good solution). Though if you want to DRY, just put your suffix into the variable. Apart from that, your way is optimal. — Yevhen Kuzmovych, Feb 01 '21 at 14:20
They appear to be separate, unrelated operations. I think the best you could do is save `'_df2` into a variable so you don't need to change it in multiple places in the future. Otherwise, I'd do it as you already are. — Carcigenicate, Feb 01 '21 at 14:21
Thanks! @YevhenKuzmovych Why is putting it into one line a bad solution? — phoebe_albeduddel, Feb 01 '21 at 14:25
@phoebe_albeduddel There's absolutely no benefit of doing that. It only worsens readability. — Yevhen Kuzmovych, Feb 01 '21 at 14:27

score 0 · Answer 1 · answered Feb 01 '21 at 14:28

0

Create a single list headed by your singleton item, universally apply the modification, then unpack in the same order.

myVariable, *myList = [x + '_df2' for x in [myVariable, *myList]]

I would probably still prefer the two-line solution, though. You aren't just appending the same value to each element; you also need to preserve the list structure of the original list.

answered Feb 01 '21 at 14:28

chepner

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Star assignments are covered in [PEP 448](https://www.python.org/dev/peps/pep-0448/) Works the other way too: `*myList,myVariable=[e+addition for e in myList+[myVariable]]` – dawg Feb 01 '21 at 15:44

score -1 · Answer 2 · answered Feb 01 '21 at 14:20

-1

You could do the following, but as @YevhenKuzmovych says, its not a good solution.

myList, myVariable = [fruit + '_df2' for fruit in myList], myVariable + '_df2'

answered Feb 01 '21 at 14:20

Scott Hunter

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There's absolutely no benefit of doing that. There are still two operations there (3 or 4 if you count packing, unpacking). And now it's less readable. – Yevhen Kuzmovych Feb 01 '21 at 14:43

Adding a suffix to both elements in a list and to a variable at the same time

2 Answers2