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 = #"^(<\!\-\- wp:onecms\/recipe-time \{\"type\"\:\"cook\")\S(.*[a-z\:0-9\}\s])(\/\-\->)$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" <!-- wp:onecms/recipe-header {"dek":"\u003cp\u003eHungry for some \u003ca href=\u0022https://www.southernliving.com/recipes/old-fashioned-apple-pie\u0022\u003eapple pie\u003c/a\u003e? We are right there with you. Here's the recipe from the Whispering Canyon Café at Disney’s Wilderness Lodge—dessert will never be the same.\u003c/p\u003e"} /--> <!-- wp:onecms/primary-media /--> <!-- wp:onecms/recipe-media /--> <!-- wp:onecms/recipe-container --> <!-- wp:onecms/recipe-details --> <!-- wp:onecms/recipe-metadata {"yieldDescription":"Makes one 9-inch pie."} /--> <!-- wp:onecms/recipe-times --> <!-- wp:onecms/recipe-time {"type":"hands-on","days":0,"hours":0,"minutes":45} /--> <!-- wp:onecms/recipe-time {"type":"cook","days":0,"hours":1,"minutes":0} /--> <!-- /wp:onecms/recipe-times --> <!-- /wp:onecms/recipe-details --> <!-- wp:onecms/recipe-ingredients --> <!-- wp:onecms/recipe-section-header {"content":"Pie Crust"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"butter, cut into small pieces","customMeasure":"tablespoons","customQuantity":"4"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"shortening","customMeasure":"cup","customQuantity":"0.25"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"all-purpose flour","customMeasure":"cups","customQuantity":"1.75"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"sugar","customMeasure":"teaspoons","customQuantity":"4"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"coarse salt","customMeasure":"teaspoon","customQuantity":"0.13"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"2% milk","customMeasure":"cup","customQuantity":"0.33"} /--> <!-- wp:onecms/recipe-section-header {"content":"Apples"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"water","customMeasure":"cup","customQuantity":"1"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"Granny Smith apples, peeled and sliced","customQuantity":"6"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"apple pie spice","customMeasure":"teaspoon","customQuantity":"2"} /--> <!-- wp:onecms/recipe-section-header {"content":"Apple Pie Batter"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"butter, softened","customMeasure":"cup","customQuantity":"0.5"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"sugar","customMeasure":"cup","customQuantity":"0.67"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"eggs","customQuantity":"2"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"flour","customMeasure":"cups","customQuantity":"1.5"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"baking powder","customMeasure":"teaspoon","customQuantity":"1.5"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"salt","customMeasure":"teaspoon","customQuantity":"0.13"} /--> <!-- wp:onecms/recipe-ingredient-custom {"customIngredient":"heavy cream","customMeasure":"cup","customQuantity":"0.25"} /--> <!-- /wp:onecms/recipe-ingredients --> <!-- wp:onecms/recipe-nutrition {"displayNutritionRecipe":false} /--> <!-- wp:onecms/recipe-directions --> <!-- wp:onecms/recipe-direction {"directionId":"ddaa1eec-7bec-4284-b4e3-53b35cb83941","content":"\u003cstrong\u003eFOR PIE CRUST: \u003c/strong\u003e"} /--> <!-- wp:onecms/recipe-direction {"directionId":"e546e3c3-96a5-4be5-94fa-34ee625f3a48","content":"\u003cstrong\u003eFOR APPLES:\u003c/strong\u003e"} /--> <!-- wp:onecms/recipe-direction {"directionId":"49fbc0c6-12f0-420c-9dc6-19210620e023","content":"\u003cstrong\u003eFOR APPLE PIE BATTER:\u003c/strong\u003e"} /--> <!-- wp:onecms/recipe-direction {"directionId":"208717df-e3e3-43e9-a2bc-35ad854ae43c","content":"\u003cstrong\u003eFOR APPLE PIE:\u003c/strong\u003e"} /--> <!-- /wp:onecms/recipe-directions --> <!-- wp:onecms/recipe-notes --> <!-- wp:onecms/recipe-note /--> <!-- /wp:onecms/recipe-notes --> <!-- /wp:onecms/recipe-container --> """# 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