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 = '"JOB_FINISH" "9.13" 1492516700 8652537 42878 -2112536045 1 1492516484 0 0 1492516498 "ukunapul" "short" "select[type==LINUX64] rusage[mem=8000]" "" "/pkg/ice/sysadmin/bin/linux-pre-exec" "san-qp200-d5-17-01" "/prj/vlsi/memchar/memchar_sec10lpe/sllsp122_rhrh_1p100/lpe-2_0_4_0_sm-1_100/uday_MA_disk_performance_test/sram2112_s10lpellrflv1223a_rhrh/timing" "" "/prj/vlsi/memchar/memchar_sec10lpe/sllsp122_rhrh_1p100/lpe-2_0_4_0_sm-1_100/uday_MA_disk_performance_test/sram2112_s10lpellrflv1223a_rhrh/timing/lsf_logs/rf_s10lpellrflv1223a_rhrh_acc_rf_s10lpellrflv1223a_rhrh_acc_00.465v_1.050v_ffg_0c_rcw_ccw_0c_1.110_libgen.log" "" "9/1492516484.8652537" 0 1 "san-qp200-d5-2-02" 64 161.0 "Libgen:rf_s10lpellrflv1223a_rhrh_acc_rf_s10lpellrflv1223a_rhrh_acc_0 0.465v_1.050v_ffg_0c_rcw_ccw_0c_1.110 " "/prj/vlsi/memchar/memchar_lpe_run/sp_non_red/ukunapul/example_sec10lpe_ma_data/mem_libgen/5.5/perl/bin/mem_libgen -replay /prj/vlsi/memchar/memchar_sec10lpe/sllsp122_rhrh_1p100/lpe-2_0_4_0_sm-1_100/uday_MA_disk_performance_test/sram2112_s10lpellrflv1223a_rhrh/timing/tmp/replay/rf_s10lpellrflv1223a_rhrh_acc_rf_s10lpellrflv1223a_rhrh_acc_0_0.465v_1.050v_ffg_0c_rcw_ccw_0c_1.110.mem_libgen.replay" 247.719480 4.420275 238204 0 -1 0 0 970373 0 0 139344 510984 -1 0 0 0 20489 33778 -1 "" "default" 0 1 "" "" 0 2772991 4822300 "" "" "" "ipl_mem_char_sc" 0 "" 0 "" -1 "/QCOM/IPL/ipl.memory/ipl.memory.char/ipl.memory.char.nazgul_10lpe/ipl.memory.char.nazgul_10lpe.lsf.gridsdcb/ukunapul" "default" "" "" -1 "" "" 2622480 "" 0 0 10800 0 2772991 "select[((type == LINUX64 ) && (type == any)) && ((health == ok ) && (type == any))] order[-maxmem:r15s:pg] rusage[mem=8000.00] " "" -1 "" -1 0 "" "" 211 "/prj/vlsi/memchar/memchar_sec10lpe/sllsp122_rhrh_1p100/lpe-2_0_4_0_sm-1_100/uday_MA_disk_performance_test/sram2112_s10lpellrflv1223a_rhrh/timing" 0 1 "san-qp200-d5-2-02"'; my $regex = qr/\/[\w\/\-\.]*\b/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