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

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"parent\s*\{\s*type\s*\{[^{}]*subtype\s+TestSubType\s*\{[^{}]*element\s+TestElement\s*\{[^{}]*attributes\s*\{[^{}]*value\s+testvalue[^{}]*\}[^{}]*owner\s+person1" test_str = ("parent {\n" " type {\n" " subtype TestSubType {\n" " element TestElement {\n" " attributes {\n" " name testname;\n" " description testdescription;\n" " count 1234;\n" " value testvalue;\n" " }\n" " owner person1;\n" " }\n" " }\n" " subtype TestSubType1 {\n" " element TestElement1 {\n" " attributes {\n" " name testname1;\n" " description testdescription1;\n" " count 1;\n" " value 1\n" " }\n" " owner person2;\n" " }\n" " }\n" " subtype TestSubType2 {\n" " element TestElement2 {\n" " attributes {\n" " name testname2;\n" " description testdescription2;\n" " count 2;\n" " value 2\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType3 {\n" " element TestElement3 {\n" " attributes {\n" " name testname3;\n" " description testdescription3;\n" " count 3;\n" " value 3\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType3 {\n" " element TestElement4 {\n" " attributes {\n" " name testname4;\n" " description testdescription4;\n" " count 4;\n" " value 4\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType4 {\n" " element TestElement5 {\n" " attributes {\n" " name testname5;\n" " description testdescription5;\n" " count 5;\n" " value 5\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType5 {\n" " element TestElement6 {\n" " attributes {\n" " name testname6;\n" " description testdescription6;\n" " count 6;\n" " value 6\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType6 {\n" " element TestElement7 {\n" " attributes {\n" " name testname7;\n" " description testdescription7;\n" " count 7;\n" " value 7\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType7 {\n" " element TestElement8 {\n" " attributes {\n" " name testname8;\n" " description testdescription8;\n" " count 8;\n" " value 8\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType8 {\n" " element TestElement9 {\n" " attributes {\n" " name testname9;\n" " description testdescription9;\n" " count 9;\n" " value 9\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType9 {\n" " element TestElement10 {\n" " attributes {\n" " name testname10;\n" " description testdescription10;\n" " count 10;\n" " value 10\n" " }\n" " owner unknown;\n" " }\n" " }\n" " subtype TestSubType10 {\n" " element TestElement11 {\n" " attributes {\n" " name testname11;\n" " description testdescription11;\n" " count 11;\n" " value 11\n" " }\n" " owner unknown;\n" " }\n" " }\n" " }\n" "}\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # 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