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

r"
"
g

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(VRP.+|Cisco\sIOS.+)(Version\s\S+)|(HUAWEI\s\S+|cisco\s\S+)`) var str = `<RMCOVTA0201>dis ver Huawei Versatile Routing Platform Software VRP (R) software, Version 8.10 (CX600 V800R007C10) Copyright (C) 2012-2014 Huawei Technologies Co., Ltd. HUAWEI CX600-X2-M16 uptime is 902 days, 1 hour, 17 minutes CX600-X2-M16 version information: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - BKP version information: PCB Version : CX68BKP03B REV B MPU Slot Quantity : 2 NPU Slot Quantity : 2 CARD Slot Quantity : 16 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - MPU version information: MPU (Master) 19 : uptime is 902 days, 1 hour, 16 minutes StartupTime 2015/04/16 19:22:14 SDRAM Memory Size : 2048 M bytes FLASH Memory Size : 16 M bytes NVRAM Memory Size : 4096 K bytes CFCARD Memory Size : 2048 M bytes CX6D00MPUK70 version information: PCB Version : CX68MPUK REV B EPLD Version : 106 FPGA Version : 107 BootROM Version : 03.47 BootLoad Version : 03.47 MPU (Slave) 20 : uptime is 902 days, 1 hour, 14 minutes StartupTime 2015/04/16 19:24:06 SDRAM Memory Size : 2048 M bytes FLASH Memory Size : 16 M bytes NVRAM Memory Size : 4096 K bytes CFCARD Memory Size : 2048 M bytes CX6D00MPUK70 version information: PCB Version : CX68MPUK REV B EPLD Version : 106 FPGA Version : 107 BootROM Version : 03.47 BootLoad Version : 03.47 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - NPU version information: NPU 17 : uptime is 902 days, 1 hour, 14 minutes StartupTime 2015/04/16 19:24:17 Host processor : SDRAM Memory Size : 2048 M bytes Flash Memory Size : 128 M bytes LPU CR5DNPU12070 version information: PCB Version : CX68NPU120A REV BCisco IOS XR Software, Version 5.1.3[Default] RP/0/RSP0/CPU0:RMCOCEM0101#sh ver Wed Oct 4 12:47:21.939 BRT Cisco IOS XR Software, Version 5.1.3[Default] Copyright (c) 2015 by Cisco Systems, Inc. ROM: System Bootstrap, Version 0.75(c) 1994-2012 by Cisco Systems, Inc. RMCOCEM0101 uptime is 39 weeks, 2 hours, 6 minutes System image file is "disk0:asr9k-os-mbi-5.1.3.CSCur21570-1.0.0/0x100305/mbiasr9k-rsp3.vm" cisco ASR9K Series (Intel 686 F6M14S4) processor with 6291456K bytes of memory. Intel 686 F6M14S4 processor at 2127MHz, Revision 2.174 ASR 9006 DC Chassis with PEM Version 2 4 Management Ethernet 40 GigabitEthernet 8 TenGigE 8 DWDM controller(s) 8 WANPHY controller(s) 503k bytes of non-volatile configuration memory. 6220M bytes of hard disk. 12510192k bytes of disk0: (Sector size 512 bytes). 12510192k bytes of disk1: (Sector size 512 bytes). Configuration register on node 0/RSP0/CPU0 is 0x2102 Boot device on node 0/RSP0/CPU0 is disk0: Package active on node 0/RSP0/CPU0: iosxr-fwding-5.1.3.CSCur07854, V 1.0.0[SMU], Cisco Systems, at disk0:iosxr-fwding-5.1.3.CSCur07854-1.0.0 Built on Fri Oct 17 03:14:03 BRT 2014 By iox-bld1 in /scratch1/smu/EFR/smu_r51x_5_1_3/workspace for pie RP/0/RSP0/CPU0:RTARRCE0202#sh ver Wed Oct 4 13:06:41.766 BRT Cisco IOS XR Software, Version 5.1.3[Default] Copyright (c) 2015 by Cisco Systems, Inc. ROM: System Bootstrap, Version 0.71(c) 1994-2012 by Cisco Systems, Inc. RTARRCE0202 uptime is 1 year, 28 weeks, 8 hours, 58 minutes System image file is "disk0:asr9k-os-mbi-5.1.3.CSCuv70838-1.0.0/0x100305/mbiasr9k-rsp3.vm" cisco ASR9K Series (Intel 686 F6M14S4) processor with 6291456K bytes of memory. Intel 686 F6M14S4 processor at 2128MHz, Revision 2.174 ASR 9006 DC Chassis with PEM Version 2 2 Management Ethernet 20 TenGigE 20 DWDM controller(s) 20 WANPHY controller(s) 20 GigabitEthernet 503k bytes of non-volatile configuration memory. 6271M bytes of hard disk. 11817968k bytes of disk0: (Sector size 512 bytes). 11817968k bytes of disk1: (Sector size 512 bytes). Configuration register on node 0/RSP0/CPU0 is 0x2102 Boot device on node 0/RSP0/CPU0 is disk0: Package active on node 0/RSP0/CPU0: iosxr-fwding-5.1.3.CSCux30811, V 1.0.0[SMU], Cisco Systems, at disk0:iosxr-fwding-5.1.3.CSCux30811-1.0.0 Built on Fri Dec 11 19:52:18 BRTSUMMERTIME 2015 By iox-lnx-008 in /san1/smu/EFR/smu_r51x_5_1_3/workspace for pie asr9k-px-5.1.3.CSCux30811, V 1.0.0[SMU], Cisco Systems, at disk0:asr9k-px-5.1.3.CSCux30811-1.0.0 Built on Fri Dec 11 19:52:21 BRTSUMMERTIME 2015 By iox-lnx-008 in /san1/smu/EFR/smu_r51x_5_1_3/workspace for pie BFGME10#sh ver Cisco IOS Software, c7600rsp72043_rp Software (c7600rsp72043_rp-ADVENTERPRISEK9-M), Version 15.3(3)S4, RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2014 by Cisco Systems, Inc. Compiled Fri 19-Sep-14 01:29 by prod_rel_team ROM: System Bootstrap, Version 12.2(33r)SRE2, RELEASE SOFTWARE (fc1) BOOTLDR: Cisco IOS Software, c7600rsp72043_rp Software (c7600rsp72043_rp-ADVENTERPRISEK9-M), Version 15.3(3)S4, RELEASE SOFTWARE (fc1) BFGME10 uptime is 2 years, 14 weeks, 14 hours, 24 minutes Uptime for this control processor is 2 years, 14 weeks, 12 hours, 59 minutes System returned to ROM by power cycle (SP by power on) System restarted at 23:57:22 UTC Sun Jun 28 2015 System image file is "sup-bootdisk:/c7600rsp72043-adventerprisek9-mz.153-3.S4.bin" Last reload type: Normal Reload Last reload reason: power-on This product contains cryptographic features and is subject to United States and local country laws governing import, export, transfer and use. Delivery of Cisco cryptographic products does not imply third-party authority to import, export, distribute or use encryption. Importers, exporters, distributors and users are responsible for compliance with U.S. and local country laws. By using this product you agree to comply with applicable laws and regulations. If you are unable to comply with U.S. and local laws, return this product immediately. A summary of U.S. laws governing Cisco cryptographic products may be found at: http://www.cisco.com/wwl/export/crypto/tool/stqrg.html <RMAGLRA-LMPN02-01>dis <RMAGLRA-LMPN02-01>display ver Huawei Versatile Routing Platform Software VRP (R) software, Version 8.10 (CX600 V800R007C10) Copyright (C) 2012-2014 Huawei Technologies Co., Ltd. HUAWEI CX600-X2-M8 uptime is 434 days, 2 hours, 3 minutes CX600-X2-M8 version information: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - BKP version information: PCB Version : CX68BKP02B REV B MPU Slot Quantity : 2 NPU Slot Quantity : 2 CARD Slot Quantity : 8 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - MPU version information: ` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/