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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\d+/\d+/\d+" test_str = ("interface gpon_olt-1/1/1 onu 1 type ZTE-OMC3 sn ZTEGC0CD5938\n" "interface gpon_olt-1/1/1 onu 2 type ZTE-F612 sn ZTEGC8BF978F\n" "interface gpon_olt-1/1/1 onu 3 type ZTE-OMC3 sn ZTEGC8653DA1\n" "interface gpon_olt-1/1/1 onu 4 type ZTE-OMC3 sn ZTEGC4BC9D80\n" "interface gpon_olt-1/1/1 onu 5 type ZTE-F670 sn ZTEGCE8DA5F5\n" "interface gpon_olt-1/1/1 onu 7 type ZTE-F670 sn ZTEGC8509BBE\n" "interface gpon_olt-1/1/1 onu 8 type ZTE-F670 sn ZTEGC8B65274") subst = "\\1" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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