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
No Match

r"
"
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /\x1B(?:[@-Z\\-_]|\[[0-?]*[ -\/]*[@-~])/m str = 'drwxrwxr-x - sebi sebi  1 Jun 09:08 .git drwxrwxr-x - sebi sebi  6 Apr 11:13 .github .rw-rw-r-- 993 sebi sebi  6 Apr 11:13 .gitignore drwxrwxr-x - sebi sebi 21 Apr 14:54 .pytest_cache drwxrwxr-x - sebi sebi  7 Apr 17:34 .tox drwxrwxr-x - sebi sebi 21 Apr 14:24 .venv .rw-rw-r-- 1,0k sebi sebi  6 Apr 11:13 CITATION.cff drwxrwxr-x - sebi sebi  6 Apr 11:13 config drwxrwxr-x - sebi sebi  6 Apr 11:13 docs .rw-rw-r-- 35k sebi sebi  6 Apr 11:13 LICENSE drwxrwxr-x - sebi sebi  6 Apr 11:13 provisioning .rw-rw-r-- 9,1k sebi sebi  6 Apr 11:13 README.md .rw-rw-r-- 133 sebi sebi  6 Apr 11:13 requirements.txt .rwxrwxr-x 443 sebi sebi  6 Apr 11:13 run_sample_simulation .rw-rw-r-- 1,3k sebi sebi  6 Apr 11:13 setup.py drwxrwxr-x - sebi sebi  6 Apr 11:14 src drwxrwxr-x - sebi sebi  6 Apr 11:13 tools .rw-rw-r-- 526 sebi sebi  6 Apr 11:13 tox.ini .rw-rw-r-- 1,4k sebi sebi 19 Mai 09:54 windows_iso_and_openssh_update.path ' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts 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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html