Python | Exceptional Split in String

Sometimes, while working with Strings, we may need to perform the split operation. The straight forward split is easy. But sometimes, we may have a problem in which we need to perform split on certain character but have exceptions. This discusses split on comma, with exception that comma should not be enclosed by brackets. Lets discuss certain ways in which this task can be performed.

Method #1 : Using loop + strip()
This is brute force way in which we perform this task. In this we construct the each element of list as words in String accounting for brackets and comma to perform split.

# Python3 code to demonstrate working of
# Exceptional Split in String
# Using loop + split()

# initializing string
test_str = "gfg, is, (best, for), geeks"

# printing original string
print("The original string is : " + test_str)

# Exceptional Split in String
# Using loop + split()
temp = ''
res = []
check = 0
for ele in test_str:
    if ele == '(':
        check += 1
    elif ele == ')':
        check -= 1
    if ele == ', ' and check == 0:
        if temp.strip():
            res.append(temp)
        temp = ''
    else:
        temp += ele
if temp.strip():
    res.append(temp)

# printing result
print("The string after exceptional split : " + str(res))

Output :

The original string is : gfg, is, (best, for), geeks
The string after exceptional split : ['gfg', ' is', ' (best, for)', ' geeks']

Method #2 : Using regex()
This is yet another way in which this task can be performed. In this, we use a regex instead of manual brute force logic for brackets comma and omit that from getting split.

# Python3 code to demonstrate working of
# Exceptional Split in String
# Using regex()
import re

# initializing string
test_str = "gfg, is, (best, for), geeks"

# printing original string
print("The original string is : " + test_str)

# Exceptional Split in String
# Using regex()
res = re.split(r', (?!\S\)|\()', test_str)

# printing result
print("The string after exceptional split : " + str(res))

Output :

The original string is : gfg, is, (best, for), geeks
The string after exceptional split : ['gfg', ' is', ' (best, for)', ' geeks']