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

re = /\d{1,3}\.\s[a-zA-Z\d\?\.\s].+$\n\s(a?\)\s[a-zA-Z].+).+\n\s(b?\)\s[A-Za-z].+).+\n\s(c\).[a-zA-Z].+)/m str = '617. What would you like to eat for lunch? …, I don’t mind. a) Nothing b) Anything c) Something 618. Where do you want to go on holiday? … with a beach. a) Somewhere b) Nowhere 613. You look familiar. Haven’t I seen you … before? a) nowhere b) anywhere c) somewhere 614. She left the room without saying … . a) nothing b) anything c) everything 615. I have never been … more beautiful than Thailand. a) somewhere b) nowhere c) anywhere 616. Who was at the party? …, so something very bad must have happened. a) No one b) Anyone c) Everyone 617. What would you like to eat for lunch? …, I don’t mind. a) Nothing b) Anything c) Something 618. Where do you want to go on holiday? … with a beach. a) Somewhere b) Nowhere c) Anywhere 619. I have … to say to you. Goodbye! a) nothing b) everything c) something 620. I felt so good being on stage. I was sure that … was looking at me. a) someone b) everyone c) no one 621. Can you please … some money until next week? a) lend b) borrow c) give 622. I decided to invest in the commodities as the … on offer from bank was extremely low. a) tax b) rent c) interest 623. Many retailers refuse to exchange purchases unless you can show them your … . a) receipt b) bill c) Anywhere 619. I have … to say to you. Goodbye! a) nothing' # Print the match result str.scan(re) do |match| puts match.to_s end

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