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

Language

Generated Code

import re regex = re.compile(r"(?:\<intent\-filter\>)(\n|\s|\w|\W|\b|\B|.)*?(?:\<\/intent\-filter\>)") test_str = ("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n" "<manifest\n" " xmlns:android=\"http://schemas.android.com/apk/res/android\"\n" " android:versionCode=\"27\"\n" " android:versionName=\"3.3.1\"\n" " compileSdkVersion=\"28\"\n" " compileSdkVersionCodename=\"9\"\n" " package=\"xyz.omnicron.caffeinate\"\n" " platformBuildVersionCode=\"27\"\n" " platformBuildVersionName=\"3.3.1\">\n" " <uses-sdk\n" " android:minSdkVersion=\"24\"\n" " android:targetSdkVersion=\"28\"/>\n" " <uses-permission\n" " android:name=\"android.permission.WAKE_LOCK\"/>\n" " <uses-permission\n" " android:name=\"android.permission.MODIFY_AUDIO_SETTINGS\"/>\n" " <uses-permission\n" " android:name=\"android.permission.ACCESS_NOTIFICATION_POLICY\"/>\n" " <uses-permission\n" " android:name=\"android.permission.FOREGROUND_SERVICE\"/>\n" " <uses-permission\n" " android:name=\"android.permission.INTERNET\"/>\n" " <uses-permission\n" " android:name=\"android.permission.ACCESS_NETWORK_STATE\"/>\n" " <uses-permission\n" " android:name=\"com.google.android.finsky.permission.BIND_GET_INSTALL_REFERRER_SERVICE\"/>\n" " <uses-permission\n" " android:name=\"com.google.android.c2dm.permission.RECEIVE\"/>\n" " <permission\n" " android:name=\"xyz.omnicron.caffeinate.permission.C2D_MESSAGE\"\n" " android:protectionLevel=\"signature\"/>\n" " <uses-permission\n" " android:name=\"xyz.omnicron.caffeinate.permission.C2D_MESSAGE\"/>\n" " <application\n" " android:theme=\"@2131755014\"\n" " android:label=\"@2131689511\"\n" " android:icon=\"@2131623936\"\n" " android:name=\"xyz.omnicron.caffeinate.Caffeine\"\n" " allowBackup=\"true\"\n" " supportsRtl=\"true\"\n" " appComponentFactory=\"android.support.v4.app.CoreComponentFactory\">\n" " <activity\n" " android:name=\"xyz.omnicron.caffeinate.MainActivity\">\n" " <intent-filter>\n" " <action\n" " android:name=\"android.intent.action.MAIN\"/>\n" " <category\n" " android:name=\"android.intent.category.LAUNCHER\"/>\n" " </intent-filter>\n" " </activity>\n" " <receiver\n" " android:name=\"xyz.omnicron.caffeinate.ActionReceiver\"\n" " android:exported=\"true\">\n" " <intent-filter>\n" " <action\n" " android:name=\"xyz.omnicron.caffeinate.STOP_ACTION\"/>\n" " </intent-filter>\n" " </receiver>\n" " <service\n" " android:label=\"@2131689514\"\n" " android:icon=\"@2131230861\"\n" " android:name=\"xyz.omnicron.caffeinate.services.CaffeinateTileService\"\n" " android:permission=\"android.permission.BIND_QUICK_SETTINGS_TILE\">\n" " <meta-data\n" " android:name=\"android.service.quicksettings.ACTIVE_TILE\"\n" " android:value=\"false\"/>\n" " <intent-filter>\n" " <action\n" " android:name=\"android.service.quicksettings.action.QS_TILE\"/>\n" " </intent-filter>\n" " </service>\n" " <service\n" " android:label=\"@2131689583\"\n" " android:icon=\"@2131230858\"\n" " android:name=\"xyz.omnicron.caffeinate.services.SoundProfileTileService\"\n" " android:permission=\"android.permission.BIND_QUICK_SETTINGS_TILE\">\n" " <meta-data\n" " android:name=\"android.service.quicksettings.ACTIVE_TILE\"\n" " android:value=\"true\"/>\n" " <intent-filter>\n" " <action\n" " android:name=\"android.service.quicksettings.action.QS_TILE\"/>\n" " </intent-filter>\n" " </service>\n" " <service\n" " android:name=\"xyz.omnicron.caffeinate.services.CaffeinationService\"\n" " android:exported=\"false\"/>\n" " <activity\n" " android:label=\"@2131689585\"\n" " android:name=\"xyz.omnicron.caffeinate.SettingsActivity\"/>\n" " <activity\n" " android:label=\"A/B Testing Debug Screen\"\n" " android:name=\"xyz.omnicron.caffeinate.ABTestingDebugActivity\">\n" " <intent-filter>\n" " <action\n" " android:name=\"xyz.omnicron.caffeinate.ABTestingDebugActivity\"/>\n" " <category\n" " android:name=\"android.intent.category.DEFAULT\"/>\n" " </intent-filter>\n" " </activity>\n" " <activity\n" " android:theme=\"@2131755016\"\n" " android:label=\"@2131689584\"\n" " android:name=\"xyz.omnicron.caffeinate.CreditsActivity\"/>\n" " <service\n" " android:name=\"com.google.firebase.components.ComponentDiscoveryService\">\n" " <meta-data\n" " android:name=\"com.google.firebase.components:com.google.firebase.firestore.FirestoreRegistrar\"\n" " android:value=\"com.google.firebase.components.ComponentRegistrar\"/>\n" " <meta-data\n" " android:name=\"com.google.firebase.components:com.google.firebase.analytics.connector.internal.AnalyticsConnectorRegistrar\"\n" " android:value=\"com.google.firebase.components.ComponentRegistrar\"/>\n" " <meta-data\n" " android:name=\"com.google.firebase.components:com.google.firebase.iid.Registrar\"\n" " android:value=\"com.google.firebase.components.ComponentRegistrar\"/>\n" " </service>\n" " <receiver\n" " android:name=\"com.google.android.gms.measurement.AppMeasurementReceiver\"\n" " android:enabled=\"true\"\n" " android:exported=\"false\"/>\n" " <receiver\n" " android:name=\"com.google.android.gms.measurement.AppMeasurementInstallReferrerReceiver\"\n" " android:permission=\"android.permission.INSTALL_PACKAGES\"\n" " android:enabled=\"true\"\n" " android:exported=\"true\">\n" " <intent-filter>\n" " <action\n" " android:name=\"com.android.vending.INSTALL_REFERRER\"/>\n" " </intent-filter>\n" " </receiver>\n" " <service\n" " android:name=\"com.google.android.gms.measurement.AppMeasurementService\"\n" " android:enabled=\"true\"\n" " android:exported=\"false\"/>\n" " <service\n" " android:name=\"com.google.android.gms.measurement.AppMeasurementJobService\"\n" " android:permission=\"android.permission.BIND_JOB_SERVICE\"\n" " android:enabled=\"true\"\n" " android:exported=\"false\"/>\n" " <receiver\n" " android:name=\"com.google.firebase.iid.FirebaseInstanceIdReceiver\"\n" " android:permission=\"com.google.android.c2dm.permission.SEND\"\n" " android:exported=\"true\">\n" " <intent-filter>\n" " <action\n" " android:name=\"com.google.android.c2dm.intent.RECEIVE\"/>\n" " <category\n" " android:name=\"xyz.omnicron.caffeinate\"/>\n" " </intent-filter>\n" " </receiver>\n" " <service\n" " android:name=\"com.google.firebase.iid.FirebaseInstanceIdService\"\n" " android:exported=\"true\">\n" " <intent-filter\n" " android:priority=\"-500\">\n" " <action\n" " android:name=\"com.google.firebase.INSTANCE_ID_EVENT\"/>\n" " </intent-filter>\n" " </service>\n" " <activity\n" " android:theme=\"@16973840\"\n" " android:name=\"com.google.android.gms.common.api.GoogleApiActivity\"\n" " android:exported=\"false\"/>\n" " <provider\n" " android:name=\"com.google.firebase.provider.FirebaseInitProvider\"\n" " android:exported=\"false\"\n" " android:authorities=\"xyz.omnicron.caffeinate.firebaseinitprovider\"\n" " android:initOrder=\"100\"/>\n" " <meta-data\n" " android:name=\"com.google.android.gms.version\"\n" " android:value=\"@2131361800\"/>\n" " </application>\n" "</manifest>\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html