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

/
/
smg

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+\)\s*\d+\.\s+)(.*?) ISSN" test_str = ("6) 6. ACROSS LANGUAGES AND CULTURES Semiannual ISSN: 1585-1923\n" "AKADEMIAI KIADO ZRT, BUDAFOKI UT 187-189-A-3, BUDAPEST, HUNGARY, H-1117\n" "Social Sciences Citation Index\n" "Arts & Humanities Citation Index\n" "7) 7. ACTA ANALYTICA-INTERNATIONAL PERIODICAL FOR PHILOSOPHY IN\n" "THE ANALYTICAL TR ADITION\n" "Quarterly ISSN: 0353-5150\n" "SPRINGER, 233 SPRING ST, NEW YORK, USA, NY, 10013\n" "Arts & Humanities Citation Index\n" "8) 8. ACTA ARCHAEOLOGICA Annual ISSN: 0065-101X\n" "WILEY, 111 RIVER ST, HOBOKEN, USA, NJ, 07030-5774\n" "Arts & Humanities Citation Index\n" "9) 9. ACTA BOREALIA Semiannual ISSN: 0800-3831\n" "ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2-4 PARK SQUARE, MILTON PARK, ABINGDON, ENGLAND, OXON, OX14 4RN\n" "Arts & Humanities Citation Index\n" "10) 10. ACTA CLASSICA Annual ISSN: 0065-1141\n" "UNIV FREE STATE, DEPT ENG CLASSICAL LANG, PO BOX 339, BLOEMFONTEIN, SOUTH AFRICA, 9300\n" "Arts & Humanities Citation Index\n" "11) 11. ACTA HISTORICA TALLINNENSIA Annual ISSN: 1406-2925\n" "ESTONIAN ACADEMY PUBLISHERS, 6 KOHTU, TALLINN, ESTONIA, 10130\n" "Arts & Humanities Citation Index\n" "12) 12. ACTA HISTRIAE Tri-annual ISSN: 1318-0185\n" "4\n" "تاریخ انتشار: 89/2/62 پژوهشگاه و شبکه آزمایشگاهی 98/3 :Code UNIV PRIMORSKA, SCI RES CENTRE KOPER, GARIBALDIJEVA 1,\n" "KOPER, SLOVENIA, CAPODISTRIA, SI-6000\n" "Social Sciences Citation Index\n" "Arts & Humanities Citation Index\n" "13) 13. ACTA KOREANA Semiannual ISSN: 1520-7412\n" "ACADEMIA KOREANA KEIMYUNG UNIV, 1095 DALGUBEOLDAERO, DALSEO-GU, DAEGU, SOUTH KOREA, 704-701\n" "Arts & Humanities Citation Index\n" "Current Contents - Arts & Humanities\n" "14) 14. ACTA LINGUISTICA HUNGARICA Quarterly ISSN: 1216-8076\n" "AKADEMIAI KIADO ZRT, BUDAFOKI UT 187-189-A-3, BUDAPEST, HUNGARY, H-1117\n" "Social Sciences Citation Index\n" "Arts & Humanities Citation Index\n" "15)15. ACTA LITERARIA Semiannual ISSN: 0717-6848\n" "UNIV CONCEPCION, FAC HUMANIDADES ARTE, CASILLA 160-C, CORREO 3, CONCEPCION, CHILE, 00000\n" "Arts & Humanities Citation Index\n" "16) 16. ACTA MUSICOLOGICA Semiannual ISSN: 0001-6241\n" "INT MUSICOLOGICAL SOC, BOX 561, BASEL, SWITZERLAND, CH-4001\n" "Arts & Humanities Citation Index\n" "Current Contents - Arts & Humanities\n" "17) 17. ACTA ORIENTALIA ACADEMIAE SCIENTIARUM HUNGARICAE Quarterly ISSN: 1588-2667\n" "AKADEMIAI KIADO ZRT, BUDAFOKI UT 187-189-A-3, BUDAPEST, HUNGARY, H-1117\n" "Arts & Humanities Citation Index\n" "5\n" "تاریخ انتشار: 89/2/62 پژوهشگاه و شبکه آزمایشگاهی 98/3 :Code Current Contents - Arts & Humanities\n" "18) 18. ACTA PHILOSOPHICA Semiannual ISSN: 1121-2179\n" "FABRIZIO SERRA EDITORE, PO BOX NO,1, SUCC NO. 8, PISA, ITALY, I-56123\n" "Arts & Humanities Citation Index\n" "Current Contents - Arts & Humanities") subst = "" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.DOTALL | 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