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

/
/
gmi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /(.*?)((?>globalis|transnat|facili|container|LIC|trad|TNC).+?)\s+(.*?)/mi str = '- Freedom of trade - The World Trade Organisation (WTO) is allowing free trade between all countries. - This causes globalisation because allowing freedom of trade means anyone can trade with anyone and get better access to ores & minerals. --- - Containerisation - Containerisation is when products are put in big boxes to be transported all around the world. - It causes globalisation because it made it easy & cheap transport things overseas. - Lots of things were modified to fit the new containers and make it the industry standard. --- - Locating outside of home countries - Companies (e.g. IKEA) are building market, outside of where they were originally located - Locating in foreign countries can allow companies to take advantage of local suppliers and local materials. - IKEA was founded in Sweden but now sells in 38 countries like Iceland, Kuwait and Malaysia. --- - Improvements of communications - The internet and mobile phones give people more access to communication outside of their country. --- - Cheap Labour - In countries like India, China and Brazil, labour costs are much lower.' subst = '$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