Additional character "\" present when appending strings into a list python

Question

does anyone encountered this issue whereby when a string containing "\" is appended into a list, the function adds an additional "\" into the string?

file_list = ['file1.txt','file2.txt','file3.txt']
res = [] 
for i in range(len(file_list)):
    filename = file_list[i].replace(".", "\.")
    print(filename)
    res.append(filename)
    print(res)
print(res)

The result that I got from running the above was:

file1\.txt
['file1\\.txt']
file2\.txt
['file1\\.txt', 'file2\\.txt']
file3\.txt
['file1\\.txt', 'file2\\.txt', 'file3\\.txt']
['file1\\.txt', 'file2\\.txt', 'file3\\.txt']

I want to get the following result instead:

['file1\.txt', 'file2\.txt', 'file3\.txt']

UPDATE

Ran the following code, still get the same output as above. Question not answered, but closed?

file_list = ['file1.txt','file2.txt','file3.txt']
res = [] 
for i in range(len(file_list)):
    filename = file_list[i].replace(".", "\\.")
    print(filename)
    res.append(filename)
    print(res)
print(res)

The difference is merely that the single string simply prints its contents, while printing the list gives you a *repr* of the entire list. Note that one string has quotes and the other doesn’t. — deceze, Apr 29 '22 at 05:31
So are the values in the list actually having double backslash? I will be using this list for file search so having double backslash will change the meaning entirely. @deceze — Kewei, Apr 29 '22 at 05:37
You need to understand the difference between the string’s contents, and a **representation** of the string as a literal, i.e. what you’d need to type into your source code to obtain that string! The list gives you the latter; again: notice the surrounding quotes. — deceze, Apr 29 '22 at 05:57

score 0 · Accepted Answer · answered Apr 29 '22 at 05:22

0

This is a normal phenomenon. The backslash in Python is used to escape characters. To directly represent the backslash, you need to use two:

>>> len('\\')
1
>>> print('\\')
\

answered Apr 29 '22 at 05:22

Mechanic Pig

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I did, but the result is still showing double backslash @Mechanic Pig – Kewei Apr 29 '22 at 05:25
@Kewei This is a normal phenomenon. The backslash must be represented by two backslashes in the string, but if you print it out, you won't see two. – Mechanic Pig Apr 29 '22 at 05:28

Additional character "\" present when appending strings into a list python

UPDATE

1 Answers1