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
No Match

/
/
mg

Test String

Code Generator

Language

Generated Code

$re = '/^Master\/Slave Set:\s(.*?\s)\[(.*)\]\sMasters:\s\[\s(.*)\s\]\s(Slaves:\s\[\s(.*)\s\])?/m'; $str = 'Cluster name: tripleo_cluster Stack: corosync Current DC: rlpclay1ct1003 (version 1.1.18-11.el7_5.3-2b07d5c5a9) - partition with quorum Last updated: Thu Oct 18 16:37:49 2018 Last change: Tue Oct 16 14:28:04 2018 by hacluster via crmd on rlpclay1ct1002 3 nodes configured 22 resources configured Online: [ rlpclay1ct1001 rlpclay1ct1002 rlpclay1ct1003 ] Offline: [ partb ] Full list of resources: ip-172.31.2.109 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1002 Clone Set: haproxy-clone [haproxy] Started: [ rlpclay1ct1001 rlpclay1ct1002 rlpclay1ct1003 ] Master/Slave Set: galera-master [galera] Masters: [ rlpclay1ct1001 rlpclay1ct1002 rlpclay1ct1003 ] ip-172.31.8.16 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1003 ip-172.31.0.19 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1002 ip-172.31.4.106 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1003 Clone Set: rabbitmq-clone [rabbitmq] Started: [ rlpclay1ct1001 rlpclay1ct1002 rlpclay1ct1003 ] Master/Slave Set: redis-master [redis] Masters: [ rlpclay1ct1003 ] Slaves: [ rlpclay1ct1001 rlpclay1ct1002 ] ip-172.31.8.19 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1002 ip-10.195.128.10 (ocf::heartbeat:IPaddr2): Started rlpclay1ct1003 openstack-cinder-volume (systemd:openstack-cinder-volume): Started rlpclay1ct1002 my-ipmilan-for-controller0 (stonith:fence_ipmilan): Started rlpclay1ct1001 my-ipmilan-for-controller1 (stonith:fence_ipmilan): Started rlpclay1ct1001 my-ipmilan-for-controller2 (stonith:fence_ipmilan): Started rlpclay1ct1001 Daemon Status: corosync: active/enabled pacemaker: active/enabled pcsd: active/enabled '; preg_match_all($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