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"(?'DateTime'\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}).*INFO *....(?'TaskName'\w+).*KMR200_(?'MR'\d).*Target Name: (?'TargetName'\w+\-\w+)\n.*Target Type\: (?'TargetType'\w+)\n.*Cycle Time: (?'CycleTime'\d+.\d+)" test_str = ("2018-09-03 15:01:58,384 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.178 seconds\n" "2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-11\n" "2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:02:21,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.952 seconds\n" "2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-16\n" "2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:07:27,960 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 35.298 seconds\n" "2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BPRD26-1\n" "2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: TOOL\n" "2018-09-03 15:10:41,524 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 25.179 seconds\n" "2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-1\n" "2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:15:06,262 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 23.523 seconds\n" "2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-6\n" "2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:17:46,641 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.258 seconds\n" "2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-2\n" "2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:21:43,892 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.194 seconds\n" "2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-7\n" "2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:27:06,475 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.093 seconds\n" "2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-5\n" "2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:01:58,384 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.178 seconds\n" "2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-11\n" "2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:02:21,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.952 seconds\n" "2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-16\n" "2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:07:27,960 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 35.298 seconds\n" "2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BPRD26-1\n" "2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: TOOL\n" "2018-09-03 15:10:41,524 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 25.179 seconds\n" "2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-1\n" "2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:15:06,262 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 23.523 seconds\n" "2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-6\n" "2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:17:46,641 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.258 seconds\n" "2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-2\n" "2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:21:43,892 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.194 seconds\n" "2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-7\n" "2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\n" "2018-09-03 15:27:06,475 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.093 seconds\n" "2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-5\n" "2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK\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