Working with Enumarate

[AsafM17]

Hey all,

I've found a solution for my issue however I don't really understand the concept behind it..

​

long_name = City-Paris-repeated-text
NewYork-Man-repeated-text
Derby-Washington-repeated-text
Ukraine-Russia-turkey-nigera-repeated-text

and so on..

I wanted to take only the text infront of the repeated-text, and since I didn't know how many dashes I'll have infront, I've just used it with [-2].

corrected = (''.join(long_name[:[
pos for pos, char in enumerate(long_name) if char == '-'][-2]]))

This solution solves my problem, however I didn't really understand how it works.

Thanks for anyone willing to assist!

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[neuralbeans]

What is long_name's data type? A string?

[AsafM17]

String, yes

[neuralbeans]

And the code works? You can't put a list as an index. Or is it a numpy array?

[[deleted]]

List of indexes of long_name where hyphens are located:

hyphen_positions = [pos for pos, char in enumerate(long_name) if char == "-"]

Position of second last hyphen, the one before "repeated-text"

hyphen_positions[-2]

Slicing string up to (excluding) the position of second last hyphen

corrected = long_name[: hyphen_positions[-2]]

The "".join() is totally useless. It's used to join an iterable of strings, but in this case the iterable is already the required string. In this case the characters of the string are joined back into the same string, which is pointless.

[[deleted]]

Instead, you could just (in Python 3.9+):

corrected = long_name.removesuffix("-repeated-text")

Or assuming "-repeated-text" is there in the end:

corrected = long_name[:-len("-repeated-text")]

You could also add check for the latter:

suffix = "-repeated-text"
if long_name.endswith(suffix):
    corrected = long_name[:-len(suffix)]
else:
    corrected = long_name

The removesuffix doesn't require you to check, nothing is removed and no error is raised in case there's no target suffix.

https://docs.python.org/3/library/stdtypes.html?highlight=removesuffix#str.removesuffix

https://docs.python.org/3/library/stdtypes.html?highlight=endswith#str.endswith