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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)\d+[thndst]+\s+(?=district)`) var str = `assumed office\s(.*?\d{4}) \d+th.*?(?=district) in office\s(.*\d{4}) member of the u.s. house of representatives from new jersey 's 5th district incumbent assumed office january 3, 2017 preceded by scott garrett adam schiff chair of the house intelligence committee in office january 3, 2019 – january 3, 2023 preceded by devin nunes succeeded by mike turner ranking member of the house intelligence committee in office january 3, 2015 – january 3, 2019 preceded by dutch ruppersberger succeeded by devin nunes member of the u.s. house of representatives from california incumbent assumed office january 3, 2001 preceded by james e. rogan constituency 27th district (2001–2003) 29th district (2003–2013) 28th district (2013–2023) 30th district (2023–present) david valadao member of the u.s. house of representatives from california incumbent assumed office january 3, 2021 preceded by tj cox constituency 21st district (2021–2023) 22nd district (2023–present) in office january 3, 2013 – january 3, 2019 preceded by devin nunes succeeded by tj cox constituency 21st district nancy pelosi official portrait, 2019 52nd speaker of the united states house of representatives in office january 3, 2019 – january 3, 2023 preceded by paul ryan succeeded by kevin mccarthy in office january 4, 2007 – january 3, 2011 preceded by dennis hastert succeeded by john boehner bill pascrell member of the u.s. house of representatives from new jersey incumbent assumed office january 3, 1997 preceded by william j. martini constituency 8th district (1997–2013) 9th district (2013–present) roy freiman member of the new jersey general assemblyfrom the 16th district incumbent assumed office january 9, 2018serving with andrew zwicker (2018-2022)sadaf jaffer (2022-present) preceded byjack ciattarelli josh gottheimer member of the u.s. house of representativesfrom new jersey's 5th district incumbent assumed office january 3, 2017 roy freiman member of the new jersey general assemblyfrom the 16th district incumbent assumed office january 9, 2018serving with andrew zwicker (2018-2022)sadaf jaffer (2022-present) preceded byjack ciattarelli district 9,republican primary,candidates,declared billy prempeh, sales consultant, u.s. air force veteran, and nominee in 2020 and 2022[5], name: billy prempeh bonnie watson coleman member u.s. house representatives new jersey 's 12th district incumbent assumed office january 3, 2015 preceded rush holt jr. bonnie watson coleman member of the u.s. house of representatives from new jersey 's 12th district incumbent assumed office january 3, 2015 preceded by rush holt jr. tom malinowski member of the u.s. house of representatives from new jersey 's 7th district in office january 3, 2019 – january 3, 2023 preceded by leonard lance succeeded by thomas kean jr.` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/