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

/
/
m

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(\(\'DB_NAME\'\,\s\')([a-z]*)(\'\)\;)`) var str = `<?php define('WP_AUTO_UPDATE_CORE', false);// This setting was defined by WordPress Toolkit to prevent WordPress auto-updates. Do not change it to avoid conflicts with the WordPress Toolkit auto-updates feature. /** * The base configuration for WordPress * * The wp-config.php creation script uses this file during the * installation. You don't have to use the web site, you can * copy this file to "wp-config.php" and fill in the values. * * This file contains the following configurations: * * * MySQL settings * * Secret keys * * Database table prefix * * ABSPATH * * @link https://codex.wordpress.org/Editing_wp-config.php * * @package WordPress */ // ** MySQL settings - You can get this info from your web host ** // /** The name of the database for WordPress */ define('DB_NAME', '--------------'); /** MySQL database username */ define('DB_USER', '--------------'); /** MySQL database password */ define('DB_PASSWORD', '--------------'); /** MySQL hostname */ define('DB_HOST', 'srv-pleskdb15.ps.kz:--------------'); /** Database Charset to use in creating database tables. */ define('DB_CHARSET', 'utf8'); /** The Database Collate type. Don't change this if in doubt. */ define('DB_COLLATE', ''); /**#@+ * Authentication Unique Keys and Salts. * * Change these to different unique phrases! * You can generate these using the {@link https://api.wordpress.org/secret-key/1.1/salt/ WordPress.org secret-key service} * You can change these at any point in time to invalidate all existing cookies. This will force all users to have to log in again. * * @since 2.6.0 */ define('AUTH_KEY', '======================================================='); define('SECURE_AUTH_KEY', '======================================================='); define('LOGGED_IN_KEY', '======================================================='); define('NONCE_KEY', '======================================================='); define('AUTH_SALT', '======================================================='); define('SECURE_AUTH_SALT', '======================================================='); define('LOGGED_IN_SALT', '======================================================='); define('NONCE_SALT', '======================================================='); /**#@-*/ /** * WordPress Database Table prefix. * * You can have multiple installations in one database if you give each * a unique prefix. Only numbers, letters, and underscores please! */ $table_prefix = 'q3j5sI_'; /** * For developers: WordPress debugging mode. * * Change this to true to enable the display of notices during development. * It is strongly recommended that plugin and theme developers use WP_DEBUG * in their development environments. * * For information on other constants that can be used for debugging, * visit the Codex. * * @link https://codex.wordpress.org/Debugging_in_WordPress */ define('WP_DEBUG', false); /* That's all, stop editing! Happy blogging. */ /** Absolute path to the WordPress directory. */ if ( !defined('ABSPATH') ) define('ABSPATH', dirname(__FILE__) . '/'); /** Sets up WordPress vars and included files. */ require_once(ABSPATH . 'wp-settings.php'); define( 'WP_ALLOW_MULTISITE', true ); define ('FS_METHOD', 'direct'); ?>` 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/