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

/
/

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\S]{0,30}").unwrap(); let string = "</head> <body> <div id=\"kJAQ_\" class=\"z-temp\"><div id=\"zk_proc\" class=\"z-loading\"><div class=\"z-loading-indicator\"><span class=\"z-loading-icon\"></span>Processing...</div></div></div> <script class=\"z-runonce\" type=\"text/javascript\"> zkmx( [0,'kJAQ_',{dt:'z_oec',cu:'/EfectoresWeb',uu:'/EfectoresWeb/zkau',ru:'/login.isp'},[ ['zul.utl.Style','zk_comp_1',{visible:false,src:'/EfectoresWeb/css/PamiStyle.css'},[]], ['zul.wgt.Div','zk_comp_2',{id:'div',style:'width:90%;margin:0 auto 0 auto;align:center',prolog:'\\n\\t'},[ ['zul.wgt.Include','zk_comp_3',{prolog:'\\n\\t\\t',_xcnt:'<div id=\"kJAQ0\" class=\"z-temp\"><div id=\"zk_proc\" class=\"z-loading\"><div class=\"z-loading-indicator\"><span class=\"z-loading-icon\"></span>Processing...</div></div></div>',_childjs:function(){zkmx( [0,'kJAQ0',{ow:'zk_comp_3'},[ ['zul.wnd.Window','zk_comp_38',{id:'winHeader',$$onSize:false,$$onMaximize:false,$$onOpen:false,$$onMinimize:false,$$onZIndex:false,$onClose:true,$$onMove:false,prolog:'\\n\\t'},[ ['zul.box.Box','zk_comp_39',{},[ ['zul.box.Box','zk_comp_40',{id:'hbox_header',align:'end'},[ ['zul.wgt.Image','zk_comp_41',{src:'/EfectoresWeb/img/top.jpg'},[]]],'horizontal']],'vertical']]]]]); }},[]], ['zul.wnd.Window','zk_comp_4',{id:'winLogin',$onOK:true,$onClose:true,prolog:'\\n\\t \\t'},[ ['zul.box.Box','zk_comp_5',{},[ ['zul.box.Box','zk_comp_6',{id:'hbox_menu'},[],'horizontal'], ['zul.wgt.Groupbox','zk_comp_7',{$$onOpen:false,width:'890px',closable:false},[ ['zul.wgt.Caption','zk_comp_8',{id:'caption_login',sclass:'z-title',label:'Login'},[]], ['zul.grid.Grid','zk_comp_9',{$$onRender:true,$"; // 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/