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

r"
"
gm

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('^\\s+\\"#{prefix}\\.(.+)\\":', 'gm') const str = `"use strict" define -> launchOptions = (prefix) -> options = "#{prefix}.businessCredits.businessBudgetFacility": functionDetails: functionId : "be.kbc.businessCredits.businessBudgetFacility", mode: "create" "#{prefix}.businessCredits.taxPrepaymentPlan": functionDetails: functionId : "be.kbc.businessCredits.taxPrepaymentPlan", mode: "create" "#{prefix}.credits.privateCreditCardRequest.update": functionDetails: functionId : "be.kbc.credits.privateCreditCardRequest", mode: "update" "#{prefix}.credits.homeAtOnce": functionDetails: functionId : "be.kbc.credits.homeAtOnce", mode: "createRequest" "#{prefix}.credits.homeAtOnce.detailRequest": functionDetails: functionId : "be.kbc.credits.homeAtOnce", mode: "detailRequest" "#{prefix}.credits.homeAtOnce.editRequest": functionDetails: functionId : "be.kbc.credits.homeAtOnce", mode: "editRequest" "#{prefix}.credits.homeAtOnce.updateRequest": functionDetails: functionId : "be.kbc.credits.homeAtOnce", mode: "updateRequest" "#{prefix}.credits.budgetfacilitylight": functionDetails: functionId : "be.kbc.credits.budgetFacilityLight", mode: "create" "#{prefix}.credits.loaRequest": functionDetails: functionId : "be.kbc.credits.loaRequest", mode: "create" "#{prefix}.credits.loaRequest.update": functionDetails: functionId : "be.kbc.credits.loaRequest", mode: "update" "#{prefix}.doccle.doccleAccount": functionDetails: functionId : "be.kbc.doccle.doccleAccount", mode: "create" "#{prefix}.esigning.esigning": functionDetails: functionId : "be.kbc.esigning.esigning", mode: "create" "#{prefix}.esigning.esigning.createBundle": functionDetails: functionId : "be.kbc.esigning.esigning", mode: "createBundle" "#{prefix}.home.dinoHomeInsurance": functionDetails: functionId : "be.kbc.home.dinoHomeInsurance", mode: "create" "#{prefix}.home.energyRenovationAdvice": functionDetails: functionId : "be.kbc.home.era", mode: "create" "#{prefix}.insurances.smallProducts": functionDetails: functionId : "be.kbc.insurances.smallProducts", mode: "create" "#{prefix}.insurances.smallproducts.external": functionDetails: functionId : "be.kbc.insurances.smallProducts", mode: "create" "#{prefix}.insurances.insurancesUpsell": functionDetails: functionId : "be.kbc.insurances.insurancesUpsell", mode: "create" "#{prefix}.investments.buycooperativeshares": functionDetails: functionId : "be.kbc.investments.buyCooperativeShares", mode: "create" "#{prefix}.savings.acceptSavingsAccount": functionDetails: functionId : "be.kbc.savings.acceptSavingsAccount", mode: "create" "#{prefix}.savings.manageAccountInsurance": functionDetails: functionId : "be.kbc.savings.manageAccountInsurance", mode: "create" "#{prefix}.savings.manageAccountInsurance.delete": functionDetails: functionId : "be.kbc.savings.manageAccountInsurance", mode: "delete" "#{prefix}.savings.openSavingsAccount": functionDetails: functionId : "be.kbc.savings.openSavingsAccount", mode: "create" "#{prefix}.savings.settleSavingsAccount": functionDetails: functionId : "be.kbc.savings.settleSavingsAccount", mode: "create" "#{prefix}.payments.businessAccountRequest": functionDetails: functionId : "be.kbc.payments.businessAccountRequest", mode: "create" "#{prefix}.payments.cardPhoto": functionDetails: functionId : "be.kbc.payments.cardPhoto", mode: "create" "#{prefix}.payments.preaccountrequest": functionDetails: functionId : "be.kbc.payments.preAccountRequest", mode: "create" "#{prefix}.payments.privateAccountRequest": functionDetails: functionId : "be.kbc.payments.privateAccountRequest", mode: "create" "#{prefix}.payments.businessCreditCardRequest": functionDetails: functionId : "be.kbc.payments.businessCreditCardRequest", mode: "create" "#{prefix}.payments.preCardRequest": functionDetails: functionId : "be.kbc.payments.preCardRequest", mode: "create" "#{prefix}.payments.preCardRequest.createReplacement": functionDetails: functionId : "be.kbc.payments.preCardRequest", mode: "createReplacement" "#{prefix}.vehicle.dinoCarInsurance": functionDetails: functionId : "be.kbc.vehicle.dinoCarInsurance", mode: "create" "#{prefix}.vehicle.privateLease": functionDetails: functionId : "be.kbc.vehicle.privateLease", mode: "create" "#{prefix}.vehicle.privateLease.update": functionDetails: functionId : "be.kbc.vehicle.privateLease", mode: "update" # Note: the deeplinks below are for local development testing only, the won't be available in the pillars # coffeelint: disable=no_backticks \`//>>includeStart("local", pragmas.local)\` options["#{prefix}.credits.genericRequest"] = functionDetails: functionId : "be.kbc.credits.genericRequest", mode: "create" options["#{prefix}.credits.genericRequest.continue"] = functionDetails: functionId : "be.kbc.credits.genericRequest", mode: "continue" \`//>>includeEnd("local")\` return options return launchOptions `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions