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)<a class="list-group-item list-group-item-action " href="https:\/\/moodle-hs-ulm\.de\/course\/view\.php\?id=([0-9]*)"(?:.*\s){7}<span class="media-body ">([^<]*)<\/span>"#).unwrap(); let string = "<nav class=\"list-group\"> <a class=\"list-group-item list-group-item-action active\" href=\"https://moodle-hs-ulm.de/\" data-key=\"home\" data-isexpandable=\"0\" data-indent=\"0\" data-showdivider=\"0\" data-type=\"1\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"1\" data-isactive=\"1\" data-hidden=\"0\" data-preceedwithhr=\"0\"> <div class=\"m-l-0\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-home fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body font-weight-bold\">Startseite</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/my/\" data-key=\"home\" data-isexpandable=\"0\" data-indent=\"0\" data-showdivider=\"0\" data-type=\"70\" data-nodetype=\"0\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"home\"> <div class=\"m-l-0\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-tachometer fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Dashboard</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/calendar/view.php?view=month\" data-key=\"calendar\" data-isexpandable=\"0\" data-indent=\"0\" data-showdivider=\"0\" data-type=\"60\" data-nodetype=\"0\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"1\"> <div class=\"m-l-0\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-calendar fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Kalender</span> </div> </div> </a> <div class=\"list-group-item\" data-key=\"mycourses\" data-isexpandable=\"1\" data-indent=\"0\" data-showdivider=\"0\" data-type=\"0\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"1\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"home\"> <div class=\"m-l-0\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body\">Meine Kurse</span> </div> </div> </div> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=88\" data-key=\"88\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Algorithmen und Datenstrukturen INF3 (WS18/19)</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=397\" data-key=\"397\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Analysis 2 für Informatiker</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=646\" data-key=\"646\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Daba</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=67\" data-key=\"67\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Einführung in MATLAB</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=551\" data-key=\"551\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">i²</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=277\" data-key=\"277\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Mobile App Dev</span> </div> </div> </a> <a class=\"list-group-item list-group-item-action \" href=\"https://moodle-hs-ulm.de/course/view.php?id=631\" data-key=\"631\" data-isexpandable=\"0\" data-indent=\"1\" data-showdivider=\"0\" data-type=\"20\" data-nodetype=\"1\" data-collapse=\"0\" data-forceopen=\"0\" data-isactive=\"0\" data-hidden=\"0\" data-preceedwithhr=\"0\" data-parent-key=\"mycourses\"> <div class=\"m-l-1\"> <div class=\"media\"> <span class=\"media-left\"> <i class=\"icon fa fa-graduation-cap fa-fw \" aria-hidden=\"true\" aria-label=\"\"></i> </span> <span class=\"media-body \">Programmieren III / INF3A</span> </div> </div> </a> </nav>"; // 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/