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"
"

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?<=application: label=')(.+?)(?=')`) var str = `package: name='com.ghisler.android.TotalCommander' versionCode='160' versionName='2.72' platformBuildVersionName='6.0-2166767' install-location:'auto' sdkVersion:'3' targetSdkVersion:'23' uses-permission: name='android.permission.WRITE_EXTERNAL_STORAGE' uses-permission: name='android.permission.BLUETOOTH_ADMIN' uses-permission: name='android.permission.BLUETOOTH' uses-permission: name='android.permission.INTERNET' uses-permission: name='android.permission.ACCESS_NETWORK_STATE' uses-permission: name='android.permission.WAKE_LOCK' uses-permission: name='android.permission.ACCESS_SUPERUSER' uses-permission: name='com.android.launcher.permission.INSTALL_SHORTCUT' uses-permission: name='com.ghisler.tcplugins.restricted' application-label:'Total Commander' application-icon-120:'res/drawable-ldpi-v4/icon.png' application-icon-160:'res/drawable-v11/icon.png' application-icon-240:'res/drawable-hdpi-v11/icon.png' application-icon-320:'res/drawable-xhdpi-v11/icon.png' application-icon-480:'res/drawable-xxhdpi-v11/icon.png' application-icon-640:'res/drawable-xxhdpi-v11/icon.png' application: label='Total Commander' icon='res/drawable-v11/icon.png' launchable-activity: name='com.ghisler.android.TotalCommander.TotalCommander' label='Total Commander' icon='' leanback-launchable-activity: name='com.ghisler.android.TotalCommander.TotalCommander' label='Total Commander' icon='' banner='' uses-permission: name='android.permission.READ_EXTERNAL_STORAGE' uses-implied-permission: name='android.permission.READ_EXTERNAL_STORAGE' reason='requested WRITE_EXTERNAL_STORAGE' feature-group: label='' uses-feature-not-required: name='android.hardware.bluetooth' uses-feature-not-required: name='android.hardware.touchscreen' main other-activities other-receivers other-services supports-screens: 'small' 'normal' 'large' 'xlarge' supports-any-density: 'true' locales: '--_--' 'da' 'ja' 'id' 'be' 'de' 'he' 'bg' 'vi' 'sk' 'uk' 'el' 'nl' 'pl' 'sl' 'ko' 'ro' 'fr' 'hr' 'sr' 'tr' 'cs' 'es' 'it' 'lt' 'hu' 'ru' 'sv' 'iw' 'zh-CN' 'pt-BR' 'pt-PT' 'zh-TW' densities: '120' '160' '240' '320' '480' '640' native-code: 'armeabi' 'mips' 'x86' ` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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 Golang, please visit: https://golang.org/pkg/regexp/