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

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #".*-> addField\(('\S*').*?, \['type' => new (\S*?)Type.*"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" -> addField('id' , ['type' => new IntType , 'description' => __('id')]) -> addField('type_mandaat' , ['type' => new StringType , 'description' => __('type mandaat')]) -> addField('bedrag' , ['type' => new BedragType , 'description' => __('bedrag')]) -> addField('datum_expertise_plaatsgevonden' , ['type' => new DateType , 'description' => __('datum van expertise')]) -> addField('datum_ontvangst_rapport' , ['type' => new DateType , 'description' => __('datum van ontvangst rapport')]) -> addField('omschrijving' , ['type' => new StringType , 'description' => __('omschrijving')]) -> addField('wrakwaarde' , ['type' => new BedragType , 'description' => __('wrakwaarde')]) -> addField('forfait' , ['type' => new BooleanType , 'description' => __('forfait')]) -> addField('total_loss' , ['type' => new BooleanType , 'description' => __('total loss')]) -> addField('kosten_expertise' , ['type' => new FloatType , 'description' => __('kosten expertise')]) -> addField('experts' , ['type' => new ListType(new ExpertInput), 'description' => __('experts')]); """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"\1 => ['type' => '\2'],"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) print(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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression