python regex search code example

Example 1: Using the Python string below to perform a search using a regular expression that you create. search_string=’’’This is a string to search for a regular expression like regular expression or regular-expression or regular:expression or regular&expression’’’

match1 = re.findall(pattern, search_string)
if match1 != None:
  print(pattern + 'matched')
else:
  print(pattern + 'did not match')

Example 2: python regular expression

import re

# The string you want to find a pattern within
test_string = 'Hello greppers!'

# Creating a regular expression pattern
# This is a simple one which finds "Hello"
pattern = re.compile(r'Hello')

# This locates and returns all the occurences of the pattern
# within the test_string
match = pattern.finditer(test_string)

# Outputs all the ocurrences which were returned as 
# as match objects
for match in matches:
  print(match)

Example 3: python re compile

import re
#	Compile a regular expression pattern into a regular expression object, which can be used for matching using its match(), search() and other methods, described below.

prog = re.compile(pattern)
result = prog.match(string)

#	is equivalent to

result = re.match(pattern, string)

Example 4: python .findall

## Search for pattern 'bb' in string 'aabbcc'.
  ## All of the pattern must match, but it may appear anywhere.
  ## On success, match.group() is matched text.
  match = re.search(r'bb', 'aabbcc') # found, match.group() == "bb"
  match = re.search(r'cd', 'aabbcc') # not found, match == None

  ## . = any char but \n
  match = re.search(r'...c', 'aabbcc') # found, match.group() == "abbc"

  ## \d = digit char, \w = word char
  match = re.search(r'\d\d\d', 'p123g') # found, match.group() == "123"
  match = re.search(r'\w\w\w', '@@abcd!!') # found, match.group() == "abc"

Example 5: Python Regex documentation\

>>> import re
>>> m = re.search('(?<=abc)def', 'abcdef')
>>> m.group(0)
'def'

Example 6: re python3

import re
>>> m = re.search('(?<=abc)def', 'abcdef')
>>> m.group(0)
'def'