Regular Expressions 101

1st Alternative^\n

^start of string

\na line-feed (newline) character (ASCII 10)

2nd Alternative\n$

\na line-feed (newline) character (ASCII 10)

$end of string, or before its final line terminator

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

^\n|\n$

New


import regex as re
from colorama import Fore, Back

def red(s):
    return Back.RED + s + Back.RESET

with open('/tmp/1.py', 'r') as f:
    data = f.read()

print(
    re.sub(r'(^\n|\n$)', red(r'\1'), data)
)

Substitution


import regex as re
from colorama import Fore, Back

def red(s):
    return Back.RED + s + Back.RESET

with open('/tmp/1.py', 'r') as f:
    data = f.read()

print(
    re.sub(r'(^\n|\n$)', red(r'\1'), data)
)