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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<search> <query>index=_internal [`set_local_host`] source=*license_usage.log* type="Usage" | eval h=if(len(h)=0 OR isnull(h),"(SQUASHED)",h) | eval s=if(len(s)=0 OR isnull(s),"(SQUASHED)",s) | eval idx=if(len(idx)=0 OR isnull(idx),"(UNKNOWN)",idx) | bin _time span=1d | stats sum(b) as b by _time, pool, s, st, h, idx | timechart span=1d sum(b) AS volumeB by st fixedrange=false | join type=outer _time [search index=_internal [`set_local_host`] source=*license_usage.log* type="RolloverSummary" | eval _time=_time - 43200 | bin _time span=1d | stats latest(stacksz) AS "stack size" by _time] | fields - _timediff | foreach * [eval &lt;&lt;FIELD&gt;&gt;=round(\'&lt;&lt;FIELD&gt;&gt;\'/1024/1024/1024, 3)] </query> <earliest>$central_time.earliest$</earliest> <latest>$central_time.latest$</latest> <sampleRatio>1</sampleRatio> </search> <option name="charting.axisLabelsX.majorLabelStyle.overflowMode">ellipsisNone</option> <option name="charting.chart.stackMode">stacked</option> <option name="charting.chart.style">shiny</option> <option name="trellis.scales.shared">1</option> <option name="trellis.size">medium</option> </chart> </panel> </row> <row> <panel> <chart> <search> <query>index=_introspection sourcetype=splunk_resource_usage component=hostwide saxsa | eval tcu = (\'data.cpu_system_pct\' + \'data.cpu_user_pct\') | timechart limit=0 span=1d avg(tcu) by host</query> <earliest>$central_time.earliest$</earliest> <latest>$central_time.latest$</latest> <sampleRatio>1</sampleRatio> </search>'; my $regex = qr/<(?!query).*(?<!<\/query)(?R)*>/mp; 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