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

/
/

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?m)^Ingredients\R((?>(?!Ingredients$).*\R)+?)Preparation$"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" Recipes & Menus Expert Advice Ingredients Holidays & Events Community Video SUMMER COOKING Lentil and Brown Rice Soup Gourmet January 1991 3.5/4 reviews (83) 90% make it again Some soups genuinely do inspire a devotion akin to love, and this is one of them. In the cold of winter, when Gourmet editors ponder the matter of what soup Cook Reviews (83) YIELD: Makes about 14 cups, serving 6 to 8 Ingredients 5 cups chicken broth 1 1/2 cups lentils, picked over and rinsed 1 cup brown rice a 32- to 35-ounce can tomatoes, drained, reserving the juice, and chopped 3 carrots, halved lengthwise and cut crosswise into 1/4-inch pieces 1 onion, chopped 1 stalk of celery, chopped 3 garlic cloves, minced 1/2 teaspoon crumbled dried basil 1/2 teaspoon crumbled dried orégano 1/4 teaspoon crumbled dried thyme 1 bay leaf 1/2 cup minced fresh parsley leaves 2 tablespoons cider vinegar, or to taste Preparation In a heavy kettle combine the broth, 3 cups water, the lentils, the rice, the tomatoes with the reserved juice, """# let stringRange = NSRange(location: 0, length: testString.utf16.count) if let firstMatch = regex.firstMatch(in: testString, range: stringRange) { let result: [String] = (1 ..< firstMatch.numberOfRanges).map { (testString as NSString).substring(with: firstMatch.range(at: $0)) } print(result) } else { print("No matches were found.") }

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