What is Regular Expression?

Regular Expression. Source: hamradio.my

Regular Expression (RegEx) is an order of special character that use search pattern to find string or group of strings.

• We will be able to detect whether there is text by matching it with certain pattern and also able to divide the pattern into one or more sub-pattern.
• Python also provides re module that support the utilization of regex in Python.
• The main function is to offer searching, where it will be needed of regular expression and string.

Example

import re
s = 'MySkill: portal for any learning path'

match = re.search(r'portal', s)

print('Start Index:', match.start())
print('End Index:', match.end())

Start Index: 9
End Index: 15

The above code gave early index and last index from string portal.

Note: Here r character (r'portal') means raw, not regex. Raw string is little different from ordinary string, it will not interpret character\ as runaway character. This because the expression of the machine use character \ as the purpose to runway itself.