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]
  • 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
Processing...

Test String

Substitution
Processing...

Code Generator

Generated Code

re = /interface (\w+)(\s+){([?\w\s\d:;()\[\]=>\.]*)};/m str = '/** * Analytic instance returned from initialization * @property identify - Identify a user * @property track - Track an analytics event * @property page - Trigger page view * @property user - Get user data * @property reset - Clear information about user & reset analytics * @property ready - Fire callback on analytics ready event * @property on - Fire callback on analytics lifecycle events. * @property once - Fire callback on analytics lifecycle events once. * @property getState - Get data about user, activity, or context. * @property storage - storage methods * @property plugins - plugin methods */ export interface AnalyticsInstance { identify: Identify; track: Track; page: Page; user: User; reset: Reset; ready: Ready; on: On; once: Once; getState: GetState; storage: Storage; plugins: Plugins; }; interface AnalyticsPluginBase { name: string; EVENTS?: any; config?: any; initialize?: (...params: any[]) => any; page?: (...params: any[]) => any; track?: (...params: any[]) => any; identify?: (...params: any[]) => any; loaded?: (...params: any[]) => any; ready?: (...params: any[]) => any; };' subst = 'interface $1$2{$3}' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html