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

r"
"
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"\S+\.(?:png|jpe?g|gif|bmp|mp4|avi|flv)\b"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" /mnt/data/Content: ManifestFile.txt kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4 tmp_content default_55a655f340908dce55d10a191b6a0140 price-tags_b3c756dda783ad0691163a900fb5fe15 /mnt/data/Content/default_55a655f340908dce55d10a191b6a0140: LayoutFile_34450b33c8b44af409abb057ddedfdfe.txt blank_decommissioned.jpeg tmp_content ManifestFile.txt blank_unregistered.png /mnt/data/Content/default_55a655f340908dce55d10a191b6a0140/tmp_content: /mnt/data/Content/kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4: 0001111084948-kompass-LARGE.avi 0076738703404-kompass-LARGE.png LayoutFile_7c1b3793e49204982e0e41923303c17b.txt 0001111087321-kompass-LARGE.jpg 0076738703419-kompass-LARGE.mp4 ManifestFile.txt 0001111087325-kompass-LARGE.png 0076738703420-kompass-LARGE.png tmp_content /mnt/data/Content/kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4/tmp_content: /mnt/data/Content/price-tags_b3c756dda783ad0691163a900fb5fe15: 0001111084948-consumer-large.png 0076738703404-consumer-large.png LayoutFile_a694b1e05d08705aaf4dd589ac61d493.txt 0001111087321-consumer-large.png 0076738703419-consumer-large.avi ManifestFile.txt 0001111087325-consumer-large.mp4 0076738703420-consumer-large.png tmp_content /mnt/data/Content/price-tags_b3c756dda783ad0691163a900fb5fe15/tmp_content: /mnt/data/Content/tmp_content: """# 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