Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r""" {%\ (if)[\s\S]*?{%\ end\1\ %}| {%.+?%}| {{.+?}} """, flags=re.VERBOSE) test_str = ("<div class=\"post-preview\">\n" " <div class=\"post-title\">\n" " <div class=\"post-name\">\n" " <a href=\"{{ post.url }}\">{{ post.title }}</a>\n" " </div>\n" " <div class=\"post-date\">\n" " {% include time.html %}\n" " </div>\n" " </div>\n\n" " <div class=\"post-snippet\">\n" " {% if post.content contains '<!--break-->' %}\n" " {{ post.content | split:'<!--break-->' | first }}\n" " <div class=\"post-readmore\">\n" " <a href=\"{{ post.url }}\">read more-></a>\n" " </div>\n" " {% endif %}\n" " </div>\n" " {% include post-meta.html %}\n" "</div>") subst = "" result = regex.sub(subst, test_str) if result: print(result)

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html