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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Generated Code

use strict; my $str = '<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="27" android:versionName="3.3.1" compileSdkVersion="28" compileSdkVersionCodename="9" package="xyz.omnicron.caffeinate" platformBuildVersionCode="27" platformBuildVersionName="3.3.1"> <uses-sdk android:minSdkVersion="24" android:targetSdkVersion="28"/> <uses-permission android:name="android.permission.WAKE_LOCK"/> <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS"/> <uses-permission android:name="android.permission.ACCESS_NOTIFICATION_POLICY"/> <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/> <uses-permission android:name="android.permission.INTERNET"/> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/> <uses-permission android:name="com.google.android.finsky.permission.BIND_GET_INSTALL_REFERRER_SERVICE"/> <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE"/> <permission android:name="xyz.omnicron.caffeinate.permission.C2D_MESSAGE" android:protectionLevel="signature"/> <uses-permission android:name="xyz.omnicron.caffeinate.permission.C2D_MESSAGE"/> <application android:theme="@2131755014" android:label="@2131689511" android:icon="@2131623936" android:name="xyz.omnicron.caffeinate.Caffeine" allowBackup="true" supportsRtl="true" appComponentFactory="android.support.v4.app.CoreComponentFactory"> <activity android:name="xyz.omnicron.caffeinate.MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN"/> <category android:name="android.intent.category.LAUNCHER"/> </intent-filter> </activity> <receiver android:name="xyz.omnicron.caffeinate.ActionReceiver" android:exported="true"> <intent-filter> <action android:name="xyz.omnicron.caffeinate.STOP_ACTION"/> </intent-filter> </receiver> <service android:label="@2131689514" android:icon="@2131230861" android:name="xyz.omnicron.caffeinate.services.CaffeinateTileService" android:permission="android.permission.BIND_QUICK_SETTINGS_TILE"> <meta-data android:name="android.service.quicksettings.ACTIVE_TILE" android:value="false"/> <intent-filter> <action android:name="android.service.quicksettings.action.QS_TILE"/> </intent-filter> </service> <service android:label="@2131689583" android:icon="@2131230858" android:name="xyz.omnicron.caffeinate.services.SoundProfileTileService" android:permission="android.permission.BIND_QUICK_SETTINGS_TILE"> <meta-data android:name="android.service.quicksettings.ACTIVE_TILE" android:value="true"/> <intent-filter> <action android:name="android.service.quicksettings.action.QS_TILE"/> </intent-filter> </service> <service android:name="xyz.omnicron.caffeinate.services.CaffeinationService" android:exported="false"/> <activity android:label="@2131689585" android:name="xyz.omnicron.caffeinate.SettingsActivity"/> <activity android:label="A/B Testing Debug Screen" android:name="xyz.omnicron.caffeinate.ABTestingDebugActivity"> <intent-filter> <action android:name="xyz.omnicron.caffeinate.ABTestingDebugActivity"/> <category android:name="android.intent.category.DEFAULT"/> </intent-filter> </activity> <activity android:theme="@2131755016" android:label="@2131689584" android:name="xyz.omnicron.caffeinate.CreditsActivity"/> <service android:name="com.google.firebase.components.ComponentDiscoveryService"> <meta-data android:name="com.google.firebase.components:com.google.firebase.firestore.FirestoreRegistrar" android:value="com.google.firebase.components.ComponentRegistrar"/> <meta-data android:name="com.google.firebase.components:com.google.firebase.analytics.connector.internal.AnalyticsConnectorRegistrar" android:value="com.google.firebase.components.ComponentRegistrar"/> <meta-data android:name="com.google.firebase.components:com.google.firebase.iid.Registrar" android:value="com.google.firebase.components.ComponentRegistrar"/> </service> <receiver android:name="com.google.android.gms.measurement.AppMeasurementReceiver" android:enabled="true" android:exported="false"/> <receiver android:name="com.google.android.gms.measurement.AppMeasurementInstallReferrerReceiver" android:permission="android.permission.INSTALL_PACKAGES" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="com.android.vending.INSTALL_REFERRER"/> </intent-filter> </receiver> <service android:name="com.google.android.gms.measurement.AppMeasurementService" android:enabled="true" android:exported="false"/> <service android:name="com.google.android.gms.measurement.AppMeasurementJobService" android:permission="android.permission.BIND_JOB_SERVICE" android:enabled="true" android:exported="false"/> <receiver android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver" android:permission="com.google.android.c2dm.permission.SEND" android:exported="true"> <intent-filter> <action android:name="com.google.android.c2dm.intent.RECEIVE"/> <category android:name="xyz.omnicron.caffeinate"/> </intent-filter> </receiver> <service android:name="com.google.firebase.iid.FirebaseInstanceIdService" android:exported="true"> <intent-filter android:priority="-500"> <action android:name="com.google.firebase.INSTANCE_ID_EVENT"/> </intent-filter> </service> <activity android:theme="@16973840" android:name="com.google.android.gms.common.api.GoogleApiActivity" android:exported="false"/> <provider android:name="com.google.firebase.provider.FirebaseInitProvider" android:exported="false" android:authorities="xyz.omnicron.caffeinate.firebaseinitprovider" android:initOrder="100"/> <meta-data android:name="com.google.android.gms.version" android:value="@2131361800"/> </application> </manifest> '; my $regex = qr/(?:\<intent\-filter\>)(\n|\s|\w|\W|\b|\B|.)*?(?:\<\/intent\-filter\>)/p; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html