{"id":3198,"date":"2021-12-02T15:27:43","date_gmt":"2021-12-02T15:27:43","guid":{"rendered":"https:\/\/www.pythontutorial.net\/?page_id=3198"},"modified":"2022-02-18T07:34:10","modified_gmt":"2022-02-18T07:34:10","slug":"python-regex-alternation","status":"publish","type":"page","link":"https:\/\/www.pythontutorial.net\/python-regex\/python-regex-alternation\/","title":{"rendered":"Python Regex Alternation"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you’ll learn about Python regex alternation, which behaves like the “OR” operator in regular expressions.<\/p>\n\n\n\n

Introduction to the Python regex alternation #<\/a><\/h2>\n\n\n\n

To represent an alternation in regular expressions<\/a>, you use the pipe operator (|<\/code>). The pipe operator is called the alternation<\/strong>. It is like the or<\/code> operator in Python.<\/p>\n\n\n\n

The following regular expression uses an alternation to match either the literal string complex<\/code> and simple<\/code>:<\/p>\n\n\n

'simple|complex'<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
For example, the following program uses the above regular expression to match either the literal string simple<\/code> or complex<\/code>:<\/p>\n\n\n
import<\/span> re\n\ns = 'simple is better than complex'<\/span>\npattern = r'simple|complex'<\/span>\n\nmatches = re.findall(pattern,s)\nprint(matches)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Output:<\/p>\n\n\n
['simple'<\/span>, 'complex'<\/span>]<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Python regex alternation examples #<\/a><\/h2>\n\n\n\n
Let’s take more examples of using the regex alternation.  <\/p>\n\n\n\n
1) Use Python regex alternation for matching time in hh:mm format #<\/a><\/h3>\n\n\n\n
To match a time string in the hh:mm<\/code> format, you can combine the \\d<\/code> character set<\/a> with the quantifiers<\/a> {}<\/code>:<\/p>\n\n\n
'\\d{2}:\\d{2}'<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
In this pattern:<\/p>\n\n\n\n