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

/
/
s

Test String

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r#"(?s)(?:(?:ok|changed|fatal): \[)([A-Za-z0-9-.]+)(?:\]) => {\s+"msg": \[(.*?)\]\s+}"#).unwrap(); let string = "PLAY [Core Switch] ************************************************************* TASK [Mapping additional variables] ******************************************** ok: [acm-lab-core1.expedient.com] TASK [Setting the core number] ************************************************* ok: [acm-lab-core1.expedient.com] TASK [Create directory for configuration files] ******************************** ok: [acm-lab-core1.expedient.com] TASK [Render the trunk configuration] ****************************************** ok: [acm-lab-core1.expedient.com] TASK [Render the rollback configuration] *************************************** ok: [acm-lab-core1.expedient.com] TASK [register the configuration rendered to a variable3] ********************** changed: [acm-lab-core1.expedient.com] TASK [debug] ******************************************************************* ok: [acm-lab-core1.expedient.com] => { \"msg\": [ \"interfaces {\", \" ae10 {\", \" unit 1001 {\", \" encapsulation vlan-bridge;\", \" vlan-id 1001;\", \" }\", \" unit 1002 {\", \" encapsulation vlan-vpls;\", \" vlan-id 1002;\", \" }\", \" }\", \" irb {\", \" unit 1001 {\", \" description \\\\\\\\\\\"PUBLIC: Dunder Mifflin\\\\\\\\(/)\\\";\", \" family inet {\", \" address 206.166.155.2/29 {\", \" vrrp-group 1001 {\", \" virtual-address 206.166.155.1;\", \" priority 200;\", \" fast-interval 500;\", \" no-preempt;\", \" accept-data;\", \" }\", \" } \", \" }\", \" }\", \" } \", \"}\", \"bridge-domains {\", \" VLAN1001 {\", \" vlan-id 1001;\", \" interface ae10.1001;\", \" routing-interface irb.1001;\", \" }\", \"}\", \"routing-instances {\", \" VPLS1002 {\", \" instance-type vpls;\", \" vlan-id 1002;\", \" interface ae10.1002;\", \" protocols {\", \" vpls {\", \" encapsulation-type ethernet-vlan;\", \" interface ae10.1002;\", \" no-tunnel-services;vpls-id 1062310;mtu 9216;\", \" neighbor 206.210.84.1;\", \" }\", \" }\", \" }\", \"}\", \"protocols {\", \" bgp {\", \" group DunderMiff-vsrx {\", \" type external;\", \" import [ tag-vsrx DunderMiff-in ];\", \" export default-only;\", \" peer-as 64512;\", \" neighbor 206.166.155.5;\", \" }\", \" }\", \"}\", \"policy-options {\", \" policy-statement DunderMiff-in {\", \" term customer-networks { \", \" from {\", \" route-filter 2.2.1.0/24 exact;\", \" route-filter 2.2.1.0/24 exact;\", \" } \", \" then accept; \", \" } \", \" term deny { \", \" then reject; \", \" } \", \" } \", \"}\" ] } PLAY [Core Switch] ************************************************************* TASK [Mapping additional variables] ******************************************** ok: [acm-lab-core2.expedient.com] TASK [Setting the core number] ************************************************* ok: [acm-lab-core2.expedient.com] TASK [Create directory for configuration files] ******************************** ok: [acm-lab-core2.expedient.com] TASK [Render the trunk configuration] ****************************************** ok: [acm-lab-core2.expedient.com] TASK [Render the rollback configuration] *************************************** ok: [acm-lab-core2.expedient.com] TASK [register the configuration rendered to a variable3] ********************** changed: [acm-lab-core2.expedient.com] TASK [debug] ******************************************************************* ok: [acm-lab-core2.expedient.com] => { \"msg\": [ \"interfaces {\", \" ae10 {\", \" unit 1001 {\", \" encapsulation vlan-bridge;\", \" vlan-id 1001;\", \" }\", \" unit 1002 {\", \" encapsulation vlan-vpls;\", \" vlan-id 1002;\", \" }\", \" }\", \" irb {\", \" unit 1001 {\", \" description \\\\\\\\\\\"PUBLIC: Dunder Mifflin\\\\\\\\(/)\\\";\", \" family inet {\", \" address 206.166.155.3/29 {\", \" vrrp-group 1001 {\", \" virtual-address 206.166.155.1;\", \" priority 100;\", \" fast-interval 500;\", \" no-preempt;\", \" accept-data;\", \" }\", \" } \", \" }\", \" }\", \" } \", \"}\", \"bridge-domains {\", \" VLAN1001 {\", \" vlan-id 1001;\", \" interface ae10.1001;\", \" routing-interface irb.1001;\", \" }\", \"}\", \"routing-instances {\", \" VPLS1002 {\", \" instance-type vpls;\", \" vlan-id 1002;\", \" interface ae10.1002;\", \" protocols {\", \" vpls {\", \" encapsulation-type ethernet-vlan;\", \" interface ae10.1002;\", \" no-tunnel-services;vpls-id 1062310;mtu 9216;\", \" neighbor 206.210.84.1;\", \" }\", \" }\", \" }\", \"}\", \"protocols {\", \" bgp {\", \" group DunderMiff-vsrx {\", \" type external;\", \" import [ tag-vsrx DunderMiff-in ];\", \" export default-only;\", \" peer-as 64512;\", \" neighbor 206.166.155.5;\", \" }\", \" }\", \"}\", \"policy-options {\", \" policy-statement DunderMiff-in {\", \" term customer-networks { \", \" from {\", \" route-filter 2.2.1.0/24 exact;\", \" route-filter 2.2.1.0/24 exact;\", \" } \", \" then accept; \", \" } \", \" term deny { \", \" then reject; \", \" } \", \" } \", \"}\" ] } PLAY [Spine Switch] ************************************************************ TASK [Mapping additional variables] ******************************************** ok: [acm-lab-spine1.expedient.com] TASK [Render the trunk configuration] ****************************************** ok: [acm-lab-spine1.expedient.com] TASK [Render the rollback configuration] *************************************** ok: [acm-lab-spine1.expedient.com] TASK [Display the configuration rendered] ************************************** changed: [acm-lab-spine1.expedient.com] TASK [debug] ******************************************************************* ok: [acm-lab-spine1.expedient.com] => { \"msg\": [ \"interfaces {\", \" ae0 {\", \" unit 1001 {\", \" vlan-id 1001;\", \" }\", \" unit 1002 {\", \" vlan-id 1002;\", \" } \", \" }\", \" ae1 {\", \" unit 1001 {\", \" vlan-id 1001;\", \" }\", \" unit 1002 {\", \" vlan-id 1002;\", \" }\", \" }\", \"}\", \"vlans {\", \" VLAN1001 {\", \" vlan-id 1001;\", \" interface ae0.1001;\", \" interface ae1.1001;\", \" }\", \" VLAN1002 {\", \" vlan-id 1002;\", \" interface ae0.1002;\", \" interface ae1.1002;\", \" } \", \"}\" ] } TASK [No Deploy] *************************************************************** skipping: [acm-lab-spine1.expedient.com] TASK [debug] ******************************************************************* skipping: [acm-lab-spine1.expedient.com] PLAY [POD Switch] ************************************************************** TASK [Setting the interface range] ********************************************* ok: [acm-lab-pod1-sw.expedient.com] TASK [Mapping additional variables] ******************************************** ok: [acm-lab-pod1-sw.expedient.com] TASK [Render the trunk configuration] ****************************************** ok: [acm-lab-pod1-sw.expedient.com] TASK [Render the rollback configuration] *************************************** ok: [acm-lab-pod1-sw.expedient.com] TASK [Display the configuration rendered] ************************************** changed: [acm-lab-pod1-sw.expedient.com] TASK [debug] ******************************************************************* ok: [acm-lab-pod1-sw.expedient.com] => { \"msg\": [ \"interfaces {\", \" interface-range DVS {\", \" unit 0 {\", \" family ethernet-switching {\", \" vlan {\", \" members 1001;\", \" members 1002;\", \" members 1111;\", \" }\", \" }\", \" }\", \" } \", \" ae0 {\", \" unit 1001 {\", \" vlan-id 1001;\", \" }\", \" unit 1002 {\", \" vlan-id 1002;\", \" } \", \" }\", \"}\", \"vlans {\", \" VLAN1001 {\", \" vlan-id 1001;\", \" interface ae0.1001;\", \" }\", \" VLAN1002 {\", \" vlan-id 1002;\", \" interface ae0.1002;\", \" }\", \" VLAN1111 {\", \" vlan-id 1111;\", \" }\", \"}\" ] } PLAY [151-fw - Radius Authentication] ****************************************** TASK [Setting the interface range] ********************************************* ok: [151-fw-mgmt.expedient.com] TASK [Mapping additional variables] ******************************************** ok: [151-fw-mgmt.expedient.com] TASK [Render the trunk configuration] ****************************************** changed: [151-fw-mgmt.expedient.com] TASK [Render the rollback configuration] *************************************** changed: [151-fw-mgmt.expedient.com] TASK [Display the configuration rendered] ************************************** changed: [151-fw-mgmt.expedient.com] TASK [debug] ******************************************************************* ok: [151-fw-mgmt.expedient.com] => { \"msg\": [ \"security {\", \" zones {\", \" security-zone untrust {\", \" address-book {\", \" address dunderhead-vsrx 1.1.1.1/32;\", \" address-set CUSTCBB-Auth-Expedient-Managed-Customer-FW {\", \" address dunderhead-vsrx;\", \" }\", \" }\", \" }\", \" }\", \"}\" ] } PLAY [tdp-fw - Radius Authentication] ****************************************** TASK [Setting the interface range] ********************************************* ok: [tdp-fw-mgmt.expedient.com] TASK [Mapping additional variables] ******************************************** ok: [tdp-fw-mgmt.expedient.com] TASK [Render the trunk configuration] ****************************************** changed: [tdp-fw-mgmt.expedient.com] TASK [Render the rollback configuration] *************************************** changed: [tdp-fw-mgmt.expedient.com] TASK [Display the configuration rendered] ************************************** changed: [tdp-fw-mgmt.expedient.com] TASK [debug] ******************************************************************* ok: [tdp-fw-mgmt.expedient.com] => { \"msg\": [ \"security {\", \" zones {\", \" security-zone untrust {\", \" address-book {\", \" address dunderhead-vsrx 1.1.1.1/32;\", \" address-set CUSTCBB-Auth-Expedient-Managed-Customer-FW {\", \" address dunderhead-vsrx;\", \" }\", \" }\", \" }\", \" }\", \"}\" ] } PLAY RECAP ********************************************************************* 151-fw-mgmt.expedient.com : ok=6 changed=3 unreachable=0 failed=0 acm-lab-core1.expedient.com : ok=7 changed=1 unreachable=0 failed=0 acm-lab-core2.expedient.com : ok=7 changed=1 unreachable=0 failed=0 acm-lab-pod1-sw.expedient.com : ok=6 changed=1 unreachable=0 failed=0 acm-lab-spine1.expedient.com : ok=5 changed=1 unreachable=0 failed=0 tdp-fw-mgmt.expedient.com : ok=6 changed=3 unreachable=0 failed=0 "; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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 Rust, please visit: https://docs.rs/regex/latest/regex/