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

/
/
gm

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#"(?m)\"app\":\"splunk-kubernetes-objects\""#).unwrap(); let string = "{\"severity\":\"INFO\",\"ts\":1704101563.224535,\"logger\":\"controller\",\"msg\":\"Seccomp profile 'not configured' is not allowed for container 'splunk-fluentd-k8s-objects'. Found at: no explicit profile found. Allowed profiles: {\\\"RuntimeDefault\\\", \\\"docker/default\\\", \\\"runtime/default\\\"}\",\"process\":\"audit\",\"audit_id\":\"2024-01-01T09:32:31Z\",\"details\":{},\"event_type\":\"violation_audited\",\"constraint_group\":\"constraints.gatekeeper.sh\",\"constraint_api_version\":\"v1beta1\",\"constraint_kind\":\"K8sPSPSeccomp\",\"constraint_name\":\"cis-k8s-v1.5.1-psp-seccomp-default\",\"constraint_namespace\":\"\",\"constraint_action\":\"warn\",\"resource_group\":\"\",\"resource_api_version\":\"v1\",\"resource_kind\":\"Pod\",\"resource_namespace\":\"idmzct0-ito-utils-splunkdc-callsign\",\"resource_name\":\"gkeusr-idmzc-dev-tier0-01-splunk-kubernetes-objects-5686d96j7nj\",\"resource_labels\":{\"app\":\"splunk-kubernetes-objects\",\"engine\":\"fluentd\",\"pod-template-hash\":\"5686d96bd8\",\"release\":\"gkeusr-idmzc-dev-tier0-01\"}} Show syntax highlighted cluster_name = gkeusr-idmzc-dev-tier0-01container_name = managerhost = npool-cos-apps-medium-7b7dd5cdb8-s6lrpnamespace = gatekeeper-systempod = gatekeeper-audit-789888c597-q9vt8severity = INFOsource = /var/log/containers/gatekeeper-audit-789888c597-q9vt8_gatekeeper-system_manager-da5f687a6b53035c4299f8e3c5cc941c510756de883f2f0e68e783cd4edc7191.logsourcetype = kube:container:manager"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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/