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

/
/
ig

Test String

Code Generator

Generated Code

import Foundation let pattern = #"('providers' => \[)([^[\]]*)(\n \],)"# let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive) let testString = #""" <?php return [ /* |-------------------------------------------------------------------------- | Application Environment |-------------------------------------------------------------------------- | | This value determines the "environment" your application is currently | running in. This may determine how you prefer to configure various | services your application utilizes. Set this in your ".env" file. | */ 'env' => env('APP_ENV', 'production'), /* |-------------------------------------------------------------------------- | Application Debug Mode |-------------------------------------------------------------------------- | | When your application is in debug mode, detailed error messages with | stack traces will be shown on every error that occurs within your | application. If disabled, a simple generic error page is shown. | */ 'debug' => env('APP_DEBUG', false), /* |-------------------------------------------------------------------------- | Application URL |-------------------------------------------------------------------------- | | This URL is used by the console to properly generate URLs when using | the Artisan command line tool. You should set this to the root of | your application so that it is used when running Artisan tasks. | */ 'url' => env('API_URL', 'http://localhost'), /* |-------------------------------------------------------------------------- | Application Timezone |-------------------------------------------------------------------------- | | Here you may specify the default timezone for your application, which | will be used by the PHP date and date-time functions. We have gone | ahead and set this to a sensible default for you out of the box. | */ 'timezone' => 'CET', /* |-------------------------------------------------------------------------- | Application Locale Configuration |-------------------------------------------------------------------------- | | The application locale determines the default locale that will be used | by the translation service provider. You are free to set this value | to any of the locales which will be supported by the application. | */ 'locale' => 'fr', /* |-------------------------------------------------------------------------- | Application Fallback Locale |-------------------------------------------------------------------------- | | The fallback locale determines the locale to use when the current one | is not available. You may change the value to correspond to any of | the language folders that are provided through your application. | */ 'fallback_locale' => 'en', /* |-------------------------------------------------------------------------- | Encryption Key |-------------------------------------------------------------------------- | | This key is used by the Illuminate encrypter service and should be set | to a random, 32 character string, otherwise these encrypted strings | will not be safe. Please do this before deploying an application! | */ 'key' => env('APP_KEY'), 'cipher' => 'AES-256-CBC', /* |-------------------------------------------------------------------------- | Logging Configuration |-------------------------------------------------------------------------- | | Here you may configure the log settings for your application. Out of | the box, Laravel uses the Monolog PHP logging library. This gives | you a variety of powerful log handlers / formatters to utilize. | | Available Settings: "single", "daily", "syslog", "errorlog" | */ 'log' => env('APP_LOG', 'single'), /* |-------------------------------------------------------------------------- | Autoloaded Service Providers |-------------------------------------------------------------------------- | | The service providers listed here will be automatically loaded on the | request to your application. Feel free to add your own services to | this array to grant expanded functionality to your applications. | */ 'providers' => [ /* * Laravel Framework Service Providers... */ Illuminate\Auth\AuthServiceProvider::class, Illuminate\Broadcasting\BroadcastServiceProvider::class, Illuminate\Bus\BusServiceProvider::class, Illuminate\Cache\CacheServiceProvider::class, Illuminate\Foundation\Providers\ConsoleSupportServiceProvider::class, Illuminate\Cookie\CookieServiceProvider::class, Illuminate\Database\DatabaseServiceProvider::class, Illuminate\Encryption\EncryptionServiceProvider::class, Illuminate\Filesystem\FilesystemServiceProvider::class, Illuminate\Foundation\Providers\FoundationServiceProvider::class, Illuminate\Hashing\HashServiceProvider::class, Illuminate\Mail\MailServiceProvider::class, Illuminate\Pagination\PaginationServiceProvider::class, Illuminate\Pipeline\PipelineServiceProvider::class, Illuminate\Queue\QueueServiceProvider::class, Illuminate\Redis\RedisServiceProvider::class, Illuminate\Auth\Passwords\PasswordResetServiceProvider::class, Illuminate\Session\SessionServiceProvider::class, Illuminate\Translation\TranslationServiceProvider::class, Illuminate\Validation\ValidationServiceProvider::class, Illuminate\View\ViewServiceProvider::class, /* * Application Service Providers... */ App\Providers\AppServiceProvider::class, App\Providers\AuthServiceProvider::class, App\Providers\EventServiceProvider::class, App\Providers\RouteServiceProvider::class, ], /* |-------------------------------------------------------------------------- | Class Aliases |-------------------------------------------------------------------------- | | This array of class aliases will be registered when this application | is started. However, feel free to register as many as you wish as | the aliases are "lazy" loaded so they don't hinder performance. | */ 'aliases' => [ 'App' => Illuminate\Support\Facades\App::class, 'Artisan' => Illuminate\Support\Facades\Artisan::class, 'Auth' => Illuminate\Support\Facades\Auth::class, 'Blade' => Illuminate\Support\Facades\Blade::class, 'Cache' => Illuminate\Support\Facades\Cache::class, 'Config' => Illuminate\Support\Facades\Config::class, 'Cookie' => Illuminate\Support\Facades\Cookie::class, 'Crypt' => Illuminate\Support\Facades\Crypt::class, 'DB' => Illuminate\Support\Facades\DB::class, 'Eloquent' => Illuminate\Database\Eloquent\Model::class, 'Event' => Illuminate\Support\Facades\Event::class, 'File' => Illuminate\Support\Facades\File::class, 'Gate' => Illuminate\Support\Facades\Gate::class, 'Hash' => Illuminate\Support\Facades\Hash::class, 'Lang' => Illuminate\Support\Facades\Lang::class, 'Log' => Illuminate\Support\Facades\Log::class, 'Mail' => Illuminate\Support\Facades\Mail::class, 'Password' => Illuminate\Support\Facades\Password::class, 'Queue' => Illuminate\Support\Facades\Queue::class, 'Redirect' => Illuminate\Support\Facades\Redirect::class, 'Redis' => Illuminate\Support\Facades\Redis::class, 'Request' => Illuminate\Support\Facades\Request::class, 'Response' => Illuminate\Support\Facades\Response::class, 'Route' => Illuminate\Support\Facades\Route::class, 'Schema' => Illuminate\Support\Facades\Schema::class, 'Session' => Illuminate\Support\Facades\Session::class, 'Storage' => Illuminate\Support\Facades\Storage::class, 'URL' => Illuminate\Support\Facades\URL::class, 'Validator' => Illuminate\Support\Facades\Validator::class, 'View' => Illuminate\Support\Facades\View::class, ], ]; """# 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