Summary: You can split a string using an empty separator using –
(i) list constructor
(ii) map+lambda
(iii) regex
(iv) list comprehension
Minimal Example:
text = '12345' # Using list()
print(list(text)) # Using map+lambda
print(list(map(lambda c: c, text))) # Using list comprehension
print([x for x in text]) # Using regex
import re
# Approach 1
print([x for x in re.split('', text) if x != ''])
# Approach 2
print(re.findall('.', text))
Problem Formulation
Problem: How to split a string using an empty string as a separator?
Example: Consider the following snippet –
a = 'abcd'
print(a.split(''))
Output:
Traceback (most recent call last): File "C:\Users\SHUBHAM SAYON\PycharmProjects\Finxter\Blogs\Finxter.py", line 2, in <module> a.split('')
ValueError: empty separator
Expected Output:
['a', 'b', 'c', 'd']
So, this essentially means that when you try to split a string by using an empty string as the separator, you will get a ValueError. Thus, your task is to find out how to eliminate this error and split the string in a way such that each character of the string is separately stored as an item in a list.
Now that we have a clear picture of the problem let us dive into the solutions to solve the problem.
Method 1: Use list()
Approach: Use the list() constructor and pass the given string as an argument within it as the input, which will split the string into separate characters.
Note: list() creates a new list object that contains items obtained by iterating over the input iterable. Since a string is an iterable formed by combining a group of characters, hence, iterating over it using the list constructor yields a single character at each iteration which represents individual items in the newly formed list.
Code:
a = 'abcd'
print(list(a)) # ['a', 'b', 'c', 'd']
Related Read: Python list() — A Simple Guide with Video
Method 2: Use map() and lambda
Approach: Use the map() to execute a certain lambda function on the given string. All you need to do is to create a lambda function that simply returns the character passed to it as the input to the map object. That’s it! However, the map method will return a map object, so you must convert it to a list using the list() function.
Code:
a = 'abcd'
print(list(map(lambda c: c, a))) # ['a', 'b', 'c', 'd']
Method 3: Use a list comprehension
Approach: Use a list comprehension that returns a new list containing each character of the given string as individual items.
Code:
a = 'abcd'
print([x for x in a])
# ['a', 'b', 'c', 'd']
Related Read: List Comprehension in Python — A Helpful Illustrated Guide
Method 4: Using regex
The re.findall(pattern, string) method scans string from left to right, searching for all non-overlapping matches of the pattern. It returns a list of strings in the matching order when scanning the string from left to right.
Related Read: Python re.findall() – Everything You Need to Know
Approach: Use the regular expression re.findall('.',a) that finds all characters in the given string ‘a‘ and stires them in a list as individual items.
Code:
import re
a = 'abcd'
print(re.findall('.',a)) # ['a', 'b', 'c', 'd']
Alternatively, you can also use the split method of the regex library in a list comprehension which returns each character of the string and eliminates empty strings.
Code:
import re
a = 'abcd'
print([x for x in re.split('',a) if x!='']) # ['a', 'b', 'c', 'd']
Related Read: Python Regex Split
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Conclusion
Hurrah! We have successfully solved the given problem using as many as four (five, to be honest) different ways. I hope this article helped you and answered your queries. Please subscribe and stay tuned for more interesting articles and solutions in the future.
Happy coding! 
Regex Humor
https://www.sickgaming.net/blog/2022/11/...separator/