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

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = ##"="?(?<currentValue>[^\"\n]*)"? # renovate:(?:[\s]+datasource=[\"\']*(?<datasource>[^\s\"\']*)[\'\"]*|[\s]+depName=[\'\"]*(?<depName>[^\s\'\"]*)[\'\"]*|[\s]+registryUrl=[\'\"]*(?<registryUrl>[^\s\'\"]*)[\'\"]*|[\s]+versioning=[\'\"]*(?<versioning>[^\s\'\"]*)[\'\"]*|[\s]+extractVersion=[\'\"]*(?<extractVersion>[^\s\'\"]*)[\'\"]*)*"## let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = ##""" # different prefix (shell scripts) VERSION=0.1.0 # renovate: DEP_VERSION=0.1.0 # renovate: # different prefix (makefile) VERSION?=0.1.0 # renovate: DEP_VERSION:=0.1.0 # renovate: # order does not matter VERSION?=v1.28.0 # renovate: datasource=github-releases registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io datasource=github-releases depName=adrienverge/yamllint versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint datasource=github-releases versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver datasource=github-releases extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver extractVersion=example-v1.1.0 datasource=github-releases # values can be wrapped between " and ' VERSION?=v1.28.0 # renovate: datasource="github-releases" registryUrl="https://docker.io" depName="adrienverge/yamllint" versioning="semver" extractVersion="example-v1.1.0" VERSION?=v1.28.0 # renovate: datasource='github-releases' registryUrl='https://docker.io' depName='adrienverge/yamllint' versioning='semver' extractVersion='example-v1.1.0' VERSION?=v1.28.0 # renovate: datasource="'""'''"github-releases"'""'''" registryUrl="'""'''"https://docker.io"'""'''" depName="'""'''"adrienverge/yamllint"'""'''" versioning="'""'''"semver"'""'''" extractVersion="'""'''"example-v1.1.0"'""'''" # ignore multiple spaces VERSION?=v1.28.0 # renovate: datasource=github-releases registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io datasource=github-releases depName=adrienverge/yamllint versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint datasource=github-releases versioning=semver extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver datasource=github-releases extractVersion=example-v1.1.0 VERSION?=v1.28.0 # renovate: registryUrl=https://docker.io depName=adrienverge/yamllint versioning=semver datasource=github-releases extractVersion=example-v1.1.0 """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"$datasource $registryUrl $depName"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) 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