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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"(?<pref>京都府)?\s*(?<city>京都市)\s*(?<ward>[上中下左右]京区|東山区|南区)\s*(?<street>(?!太秦安井柳通町|嵯峨中通町)(?:(?:[一-龠々ぁ-んァ-ンノ]+(?:通|筋|小路)|[一二三四五六七八九十百千]+(?:筋|本)目|[一二三四五六七八九十百千]+丁目|[東西南北]入(?:[るルﾙ])?|[東西南北](?:裏|側)|[上下](?!丸屋町|材木町|柳町)(?:[るルﾙ]|がる)?|[一-龠々ぁ-んァ-ンノ]+(?=\s*(?:[東西南北]入|[上下](?:[るルﾙ]|がる)?)))\s*)+)?(?<town>.+)" test_str = ("京都府京都市上京区室町通一条上る小島町123-4\n" "京都府京都市上京区今出川通室町西入ル紙屋川町345-5\n" "京都府京都市上京区新町通丸太町下る春帯町678-6\n" "京都府京都市中京区烏丸通御池下る饅頭屋町789-7\n" "京都府京都市中京区三条通河原町東入ル中島町101-8\n" "京都府京都市中京区御幸町通錦小路上ル船屋町202-9\n" "京都府京都市中京区麸屋町通六角下る坂井町303-10\n" "京都府京都市下京区四条通柳馬場西入ル立売西町404-11\n" "京都府京都市下京区松原通西洞院東入ル本塩竈町505-12\n" "京都府京都市下京区花屋町通松原上る柿本町606-13\n" "京都府京都市左京区東大路通仁王門下る東門前町707-14\n" "京都府京都市左京区北大路通下鴨本通西入ル下鴨前萩町808-15\n" "京都府京都市左京区白川通今出川上る石橋町909-16\n" "京都府京都市右京区西大路通御池下る西小路町111-17\n" "京都府京都市上京区大宮通寺之内上る二丁目西入社横町２８８\n" "京都府京都市上京区大宮通寺之内下る花開院町１２６\n" "京都府京都市中京区寺町通三条上る天性寺前町５３５\n" "京都府京都市下京区烏丸通七条下る東塩小路町５９０−２\n" "京都府京都市中京区寺町通六角上る桜之町426番地\n" "京都府京都市下京区四条通室町東入函谷鉾町78番地\n" "京都府京都市上京区上ノ下立売通紙屋川東入堀川町５２７−２６\n" "京都府京都市東山区鞘町通正面下る上堀詰町２６５\n" "京都府京都市下京区松原通西洞院東入藪下町２\n" "京都府京都市下京区東中筋通花屋町下る柳町３３５−３\n" "京都府京都市下京区東洞院通四条下る元悪王子町４７−４\n" "京都市中京区河原町通姉小路上ル下丸屋町408\n" "京都市下京区木屋町五条上がる下材木町 447\n" "京都府京都市右京区太秦安井柳通町1-1番地の4\n" "京都府京都市右京区嵯峨中通町1-1番地の4\n" "京都府京都市下京区六条通烏丸西入上柳町1-1番地の4\n" "京都府京都市上京区中筋通智恵光院西入菱屋町1-1番地の4\n") subst = "${pref}${city}${ward}${town}" # 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