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

Code Generator

Language

Generated Code

import re regex = re.compile(r"<REMITReceipt(.|\n)*?<errorCount>0(.|\n)*?\/REMITReceipt>") test_str = ("\n" " \n" "=== Receipt_20150922_REMITTable1_V1_A0000668C.SI_1.xml.asc\n\n\n" "<REMITReceipt xmlns=\"http://www.acer.europa.eu/REMIT/REMITReceiptSchema_V1.xsd\">\n" " <receiptTimestamp>2015-09-22T14:25:04.009+02:00</receiptTimestamp>\n" " <rrmId>\n" " <acer>A0000668C.SI</acer>\n" " </rrmId>\n" " <receiptType>validation</receiptType>\n" " <validationReceipt>\n" " <reportedFilename>20150922_REMITTable1_V1_A0000668C.SI_1.xml.asc.pgp</reportedFilename>\n" " <reportedFileChecksum>6445BEC781F4000C7F16F8685103B2D2D4DC500B</reportedFileChecksum>\n" " <errorCount>0</errorCount>\n" " <globalReceiptItem>\n" " <logicalRecordIdentifier>FWG_L_Sep_15</logicalRecordIdentifier>\n" " <logicalRecordType>CONTRACT</logicalRecordType>\n" " <status>Accepted</status>\n" " </globalReceiptItem>\n" " </validationReceipt>\n" "</REMITReceipt>\n\n\n" "=== Receipt_20150922_REMITTable1_V1_A0000668C.SI_10.xml.asc \n\n\n" "<REMITReceipt xmlns=\"http://www.acer.europa.eu/REMIT/REMITReceiptSchema_V1.xsd\">\n" " <receiptTimestamp>2015-09-24T09:35:07.530+02:00</receiptTimestamp>\n" " <rrmId>\n" " <acer>A0000668C.SI</acer>\n" " </rrmId>\n" " <receiptType>validation</receiptType>\n" " <validationReceipt>\n" " <reportedFilename>20150922_REMITTable1_V1_A0000668C.SI_10.xml.asc.pgp</reportedFilename>\n" " <reportedFileChecksum>13F5F5D46DFC659380AD1A7982CC2F05E7E66D5E</reportedFileChecksum>\n" " <errorCount>0</errorCount>\n" " <globalReceiptItem>\n" " <logicalRecordIdentifier>4</logicalRecordIdentifier>\n" " <logicalRecordType>TRADE</logicalRecordType>\n" " <status>Accepted</status>\n" " <logicalRecordTimestamp>2015-07-14T13:12:16.223+02:00</logicalRecordTimestamp>\n" " <logicalRecordChecksum>F6A488630A39390BE48420AFFD40ED7C82D20309</logicalRecordChecksum>\n" " </globalReceiptItem>\n" " <globalReceiptItem>\n" " <logicalRecordIdentifier>3</logicalRecordIdentifier>\n" " <logicalRecordType>TRADE</logicalRecordType>\n" " <status>Accepted</status>\n" " <logicalRecordTimestamp>2015-07-14T13:12:16.223+02:00</logicalRecordTimestamp>\n" " <logicalRecordChecksum>026F539B94346186078BA906DE2F5A9F8B3E7F6E</logicalRecordChecksum>\n" " </globalReceiptItem>\n" " <globalReceiptItem>\n" " <logicalRecordIdentifier>2</logicalRecordIdentifier>\n" " <logicalRecordType>TRADE</logicalRecordType>\n" " <status>Accepted</status>\n" " <logicalRecordTimestamp>2015-07-14T08:46:40.513+02:00</logicalRecordTimestamp>\n" " <logicalRecordChecksum>0F8253A2A3C55520E4D63959E77286CA1E95622B</logicalRecordChecksum>\n" " </globalReceiptItem>\n" " <globalReceiptItem>\n" " <logicalRecordIdentifier>1</logicalRecordIdentifier>\n" " <logicalRecordType>TRADE</logicalRecordType>\n" " <status>Accepted</status>\n" " <logicalRecordTimestamp>2015-07-14T08:46:37.223+02:00</logicalRecordTimestamp>\n" " <logicalRecordChecksum>198B018687C9D97CD3EECFBACA7EA9F196B5B80F</logicalRecordChecksum>\n" " </globalReceiptItem>\n" " </validationReceipt>\n" "</REMITReceipt>\n\n\n" "=!== Receipt_20150922_REMITTable1_V1_A0000668C.SI_100.xml.asc ") match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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