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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gi

Test String

Code Generator

Language

Generated Code

const regex = /\<yes or no\. if yes, explain why\>|\<yes\/no\>/gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\<yes or no\\. if yes, explain why\\>|\\<yes\\\/no\\>', 'gi') const str = `* Document with a Yes or No if your story impacts any of the following hazard types. If yes, explain why. ** Financial: <yes or no. If yes, explain why> ** Legal/Regulatory: <yes or no. If yes, explain why> ** Data Integrity: <yes or no. If yes, explain why> ** Patient Safety: <yes or no. If yes, explain why> ** CyberSecurity/Information Security: <yes or no. If yes, explain why> * Engineer assigned to the project has added a +1 indicating that they discussed the impact this story has with regards to Hazards and agrees with the assessment. - *Financial:* <yes or no. If yes, explain why> - *Legal/Regulatory:* <yes or no. If yes, explain why> - *Data Integrity:* <yes or no. If yes, explain why> - *Patient Safety:* <yes or no. If yes, explain why> - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> - *Financial:* <yes/no> - *Legal/Regulatory:* <yes/no> - *Data Integrity:* <yes/no> - *Patient Safety:* <yes/no> - *CyberSecurity/Information Security:* <yes/no> - *Financial:* <yes or no. If yes, explain why>No - *Legal/Regulatory:* <yes or no. If yes, explain why> Yes - *Data Integrity:* No - *Patient Safety:* Yes, this was an issue because of XYZ. - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> - *Financial:* no - *Legal/Regulatory:* no - *Data Integrity:* no - *Patient Safety:* no - *CyberSecurity/Information Security:* no - *Financial:* N - *Legal/Regulatory:* N - *Data Integrity:* N - *Patient Safety:* N - *CyberSecurity/Information Security:* N - *Financial:* <yes or no. If yes, explain why>N - *Legal/Regulatory:* <yes or no. If yes, explain why> N - *Data Integrity:* <yes or no. If yes, explain why>N - *Patient Safety:* <yes or no. If yes, explain why>N - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> N - *Financial:* <yes or no. If yes, explain why> - *Legal/Regulatory:* <yes or no. If yes, explain why> - *Data Integrity:* <yes or no. If yes, explain why> - *Patient Safety:* <yes or no. If yes, explain why> - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> - *Financial:* <yes/no> - *Legal/Regulatory:* <yes/no> - *Data Integrity:* <yes/no> - *Patient Safety:* <yes/no> - *CyberSecurity/Information Security:* <yes/no> - *Financial:* <yes or no. If yes, explain why>No - *Legal/Regulatory:* <yes or no. If yes, explain why> Yes - *Data Integrity:* No - *Patient Safety:* Yes, this was an issue because of XYZ. - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> - *Financial:* no - *Legal/Regulatory:* no - *Data Integrity:* no - *Patient Safety:* no - *CyberSecurity/Information Security:* no - *Financial:* N - *Legal/Regulatory:* N - *Data Integrity:* N - *Patient Safety:* N - *CyberSecurity/Information Security:* N - *Financial:* <yes or no. If yes, explain why>N - *Legal/Regulatory:* <yes or no. If yes, explain why> N - *Data Integrity:* <yes or no. If yes, explain why>N - *Patient Safety:* <yes or no. If yes, explain why>N - *CyberSecurity/Information Security:* <yes or no. If yes, explain why> N `; // 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