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

import Foundation let pattern = #"Size: (?:\d*X[SL]|L|M|S|\d+W)(?:-(?:\d*X[LS]|L|M|S|\d+W))*,"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" Athletics, Fitted, Mesh, Feature_Moisture Wicking, Material_Polyester 100%, , Material_Polyester 100%, Material_Polyester Over 50%, School, Style_Short Sleeves, Size_2XL, Size_L, Size_M, Size_S, Size_XL, Size_XS, Size: XS-S-M-L-XL-2XL, Uniforms, Unisex, V-Neck, VisibleLogos, Youth "Weight_8-8.9oz, Adult, Age_Adult, Feature_Cotton-Combed, Embroidered, Fit_Mens, Apparel Type_Pants, Feature_Pockets, Material_Polyester 100%, , Material_Polyester Over 50%, Size: 32W, Size: 34W, Size: 36W, Size: 38W, Size: 40W, Size: 42W, Size: 44W, Size: 46W, Size: 48W, Size: 50W, Size: 50W-32W-34W-36W-38W-40W-42W-44W-46W-48W, Uniforms, Workwear" "Weight_5-5.9oz, Adult, Age_Adult, Feature_Cotton-Combed, Embroidered, Fit_Mens, Feature_Pockets, Material_Polyester 100%, , Material_Polyester Over 50%, Style_Short Sleeves, Size_2XL, Size_3XL, Size_4XL, Size_L, Size_M, Size_S, Size_XL, Uniforms, Workwear" "Weight_5-5.9oz, Adult, Age_Adult, Feature_Cotton-Combed, Syle_Long Sleeves, Fit_Mens, Feature_Pockets, Material_Polyester 100%, , Material_Polyester Over 50%, Size_2XLT, Size_LT, Size_LT-XLT-2XLT, Size_XLT, Talls, Uniforms, Workwear" "Weight_5-5.9oz, Adult, Age_Adult, Feature_Cotton-Combed, Embroidered, Syle_Long Sleeves, Fit_Mens, Feature_Pockets, Material_Polyester 100%, , Material_Polyester Over 50%, Size_2XL, Size_3XL, Size_4XL, Size_L, Size_M, Size_S, Size_XL, Uniforms, Workwear" "Weight_4-4.9oz, Adult, Age_Adult, Material_Cotton 100%, Feature_Cotton-Combed, Feature_Ringspun Cotton, Collar Style_Crewneck, Jersey, Fit_Juniors, Weight_Light(Under 5 oz), Material_Cotton 100%, Feature_No Visible Logos, Style_Short Sleeves, Feature_Side Seams, Feature_Side Seams, Size_2XL, Size_3XL, Size_L, Size_M, Size_S, Size_XL, Tag Style_Tear Away, Feature_USA Made, Womens" "Product Type_Accessories, Size_Adjustable, Adult, Age_Adult, Feature_American Made, Material_Cotton 100%, Material_Cotton Over 50%, Embroidered, GarmentWashed, Product Type_Headwear, Hat Styles_Low Profiles, Material_Cotton 100%, Feature_No Visible Logos, Hat Style_Pre-Curved Visor, Hat Style_Six Panel, Size_Size_Adjustable, UnHat Style_Structured, Feature_USA Certified, USAMade" "Product Type_Accessories, Size_Adjustable, Adult, Age_Adult, Feature_American Made, Material_Cotton 100%, Material_Cotton Over 50%, Embroidered, GarmentWashed, Product Type_Headwear, Hat Styles_Low Profiles, Material_Cotton 100%, Feature_No Visible Logos, Hat Style_Pre-Curved Visor, Style_Relaxed, Hat Style_Six Panel, Size_Size_Adjustable, UnHat Style_Structured, Feature_USA Certified, USAMade" Size: 30W-40W, """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } 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