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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = '10:50:46 AM web.2 | > creating redis session","time":"2016-05-18T17:50:46.161Z","v":0} 10:50:46 AM web.3 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28296,"level":20,"middleware":"cache-headers","msg":"Loading middleware:: cache-headers","time":"2016-05-18T17:50:46.172Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":40,"msg":"LC-SESSION: set the secret for the session cookies in the config file, check lc-session config","time":"2016-05-18T17:50:46.174Z","v":0} 10:50:46 AM web.3 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28296,"level":20,"middleware":"client-id","msg":"Loading middleware:: client-id","time":"2016-05-18T17:50:46.175Z","v":0} 10:50:46 AM web.3 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28296,"level":20,"middleware":"cookie-parser","msg":"Loading middleware:: cookie-parser","time":"2016-05-18T17:50:46.175Z","v":0} 10:50:46 AM web.3 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28296,"level":20,"middleware":"guid","msg":"Loading middleware:: guid","time":"2016-05-18T17:50:46.175Z","v":0} 10:50:46 AM web.3 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28296,"level":20,"middleware":"healthy","msg":"Loading middleware:: healthy","time":"2016-05-18T17:50:46.176Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":20,"middleware":"sso","msg":"Loading middleware:: sso","time":"2016-05-18T17:50:46.177Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":30,"msg":"SSO-MIDDLEWARE: Detecting SSO config","time":"2016-05-18T17:50:46.177Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":30,"msg":"SSO-MIDDLEWARE: enabling JANUS-SSO","time":"2016-05-18T17:50:46.179Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":20,"middleware":"timer","msg":"Loading middleware:: timer","time":"2016-05-18T17:50:46.180Z","v":0} 10:50:46 AM web.1 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28278,"level":20,"middleware":"cache-headers","msg":"Loading middleware:: cache-headers","time":"2016-05-18T17:50:46.180Z","v":0} 10:50:46 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":20,"middleware":"setTrackingData","msg":"Loading middleware:: setTrackingData","time":"2016-05-18T17:50:46.181Z","v":0} 10:50:46 AM web.1 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28278,"level":20,"middleware":"client-id","msg":"Loading middleware:: client-id","time":"2016-05-18T17:50:46.181Z","v":0} 10:50:46 AM web.1 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28278,"level":20,"middleware":"cookie-parser","msg":"Loading middleware:: cookie-parser","time":"2016-05-18T17:50:46.181Z","v":0} 10:50:46 AM web.1 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28278,"level":20,"middleware":"guid","msg":"Loading middleware:: guid","time":"2016-05-18T17:50:46.181Z","v":0} 10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5001 is DOWN, reason: Layer4 connection problem, info: "Connection refused", check duration: 0ms. 2 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:42 AM web.1 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.1 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM web.2 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.2 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM web.3 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.3 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5002 is DOWN, reason: Layer4 connection problem, info: "Connection refused", check duration: 0ms. 1 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:42 AM web.4 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.4 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:43 AM haproxy.1 | [WARNING] 138/105043 (28265) : Server nodes/node5003 is DOWN, reason: Layer4 connection problem, info: "Connection refused", check duration: 0ms. 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:43 AM haproxy.1 | [ALERT] 138/105043 (28265) : backend \'nodes\' has no server available! 10:50:43 AM web.2 | {"name":"investor-webapp-registration","hostname":"lasinvonboard101-prod.tlcinternal.com","pid":28283,"level":30,"msg":"starting server on port 5001","time":"2016-05-18T17:50:43.751Z","v":0}'; my $regex = qr/web\.\d{1,}\s+\|\s+(\{|>)/p; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html