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 = #"https:\/\/\S+\/[a-z-0-9\?=]+-+\d+-+"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #"nav="true">Upgrade</a></div></div></header><div class="js-streamItemList"><div class="streamItem streamItem--readingListPostItem js-streamItem"><section class="u-paddingTop20 u-paddingBottom20 u-borderBottomLightest u-maxWidth740"><div class="u-flexTop"><div class="u-flex1 u-width560"><a class="link link--noUnderline u-baseColor--link" href="https://becominghuman.ai/exporting-cassandra-time-series-data-to-s3-for-data-analysis-using-spark-ca9337990a21?source=bookmarks---------0---------------------"><h3 class="u-paddingTop4 u-contentSansBold u-fontSize22 u-textColorDarkest u-maxHeight2LineHeightTighter u-lineClamp2 u-textOverflowEllipsiadingTime" title="6 min read"></span></div></div><a class="link link--noUnderline u-baseColor--link" href="https://becominghuman.ai/exporting-cassandra-time-series-data-to-s3-for-data-analysis-using-spark-ca9337990a21?source=bookmarks---------0---------------------"><div class="u-flex0 u-width80 u-marginLeft40" style="height: 80px; background-image: url(&quot;https://cdn-images-1.medium.com/fit/c/72/72/1*s-_xasoH65yaxSWqmezjTA.png&quot;); background-position: 50% 50% !import1 u-width560"><a class="link link--noUnderline u-baseColor--link" href="https://hackernoon.com/how-to-create-simple-rest-apis-with-springboot-79148ac90efd?source=bookmarks---------1---------------------"><h3 class="u-paddingTop4 u-contentSansBold u-fontSize22 u-textColorDarkest u-maxHeight2LineHeightTighter u-lineClamp2 u-textOverflowEllipsis u-patime datetime="2019-01-25T23:07:22.508Z">Jan 26</time><span class="middotDivider u-marginLeft3 u-marginRight3"></span><span class="readingTime" title="7 min read"></span></div></div><a class="link link--noUnderline u-baseColor--link" href="https://hackernoon.com/how-to-create-simple-rest-apis-with-springboot-79148ac90efd?source=bookmarks---------1---------------------"><div class="u-flex0 u-width80 u-marginLeft40" style="height: 80px; background-image: url(&quot;https://cdn-images-1.medium.com/fit/c/72/72/0*3WmoDj3kwKL3koI6&quot;); background-position: 50% 50% !important;"><span class="u-textScreenReader">How to create simple rest apis with springboot</span></div></a></div><ul class="u-flexCenter u-fontSize14 u-textColorNormal"><li><button class="button button--chromeless u-baseColor--buttonNormal" data-action="remove-from-queue">Remove</button></li></ul></section></div></div></div></div></div></div>"# 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