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

/
/
gm

Test String

Code Generator

Generated Code

$re = '/^(\d{4}-\d{2}-\d{2}\s+\d{2}:\d{2}:\d{2},\d{3})\s+(INFO)\s+(THOUGHTS):\s+(.*)$/m'; $str = '2023-04-18 02:10:54,562 INFO THOUGHTS: Before proceeding, can you provide more context on what you are trying to accomplish and any variables you have available? 2023-04-18 02:10:55,002 INFO REASONING: I need more information in order to determine the best course of action. 2023-04-18 02:10:55,312 INFO PLAN: 2023-04-18 02:10:55,389 INFO - Request additional information from the user 2023-04-18 02:10:55,584 INFO CRITICISM: N/A 2023-04-18 02:10:55,671 INFO NEXT ACTION: COMMAND = do_nothing ARGUMENTS = {} 2023-04-18 02:11:01,545 INFO -=-=-=-=-=-=-= COMMAND AUTHORISED BY USER -=-=-=-=-=-=-= 2023-04-18 02:11:01,995 INFO SYSTEM: Command do_nothing returned: No action performed. 2023-04-18 02:11:30,621 INFO THOUGHTS: Clone the Nextflow DSL repository from \'https://github.com/nextflow-io/patterns\' into a local directory, so we can use it to develop the parser. 2023-04-18 02:11:31,080 INFO REASONING: We need to access the Nextflow DSL files in order to study their structure and syntax to develop the parser. 2023-04-18 02:11:31,569 INFO PLAN: 2023-04-18 02:11:31,620 INFO - Execute clone_repository command to clone the Nextflow DSL repository\\n- Store the cloned repository in a local directory for development. 2023-04-18 02:11:32,105 INFO CRITICISM: We need to ensure that the cloned repository is up-to-date and contains the necessary files required for the parser. 2023-04-18 02:11:32,546 INFO NEXT ACTION: COMMAND = clone_repository ARGUMENTS = {\'repository_url\': \'<url>\', \'clone_path\': \'<directory>\'} 2023-04-18 02:12:40,238 INFO -=-=-=-=-=-=-= COMMAND AUTHORISED BY USER -=-=-=-=-=-=-= 2023-04-18 02:12:40,681 INFO SYSTEM: Command clone_repository returned: Error: Cmd(\'git\') failed due to: exit code(128) cmdline: git clone -v -- <url> /home/appuser/auto_gpt_workspace/<directory> stderr: \'fatal: repository \'<url>\' does not exist \' 2023-04-18 02:12:54,114 INFO THOUGHTS: Let\'s try cloning the Nextflow DSL repository again. The URL must be correct for the command to work. 2023-04-18 02:12:54,534 INFO REASONING: We need to access the Nextflow DSL files to study their structure and syntax to develop the parser. 2023-04-18 02:12:55,010 INFO PLAN: 2023-04-18 02:12:55,062 INFO - Execute clone_repository command with correct URL to clone the Nextflow DSL repository\\n- Store the cloned repository in a local directory for development. 2023-04-18 02:12:55,522 INFO CRITICISM: We need to ensure that the cloned repository is up-to-date and contains the necessary files required for the parser. 2023-04-18 02:12:55,957 INFO NEXT ACTION: COMMAND = clone_repository ARGUMENTS = {\'repository_url\': \'<url>\', \'clone_path\': \'<directory>\'} 2023-04-18 02:13:21,532 INFO -=-=-=-=-=-=-= COMMAND AUTHORISED BY USER -=-=-=-=-=-=-= 2023-04-18 02:13:21,842 INFO SYSTEM: Command clone_repository returned: Error: Cmd(\'git\') failed due to: exit code(128) cmdline: git clone -v -- <url> /home/appuser/auto_gpt_workspace/<directory> stderr: \'fatal: repository \'<url>\' does not exist \''; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php