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
Processing...

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)"name"\:"(.*?)""#).unwrap(); let string = "{\"responseheader\":{\"status\":0,\"qtime\":0},\"initfailures\":{},\"status\":{\"alfresco\":{\"name\":\"alfresco\",\"instancedir\":\"/opt/alfresco-search-services/solrhome/alfresco\",\"datadir\":\"/opt/alfresco-search-services/solrhome//alfresco/\",\"config\":\"solrconfig.xml\",\"schema\":\"schema.xml\",\"starttime\":\"2021-08-19t02:12:04.560z\",\"uptime\":8396697412,\"index\":{\"numdocs\":6530,\"maxdoc\":6567,\"deleteddocs\":37,\"indexheapusagebytes\":-1,\"version\":8008,\"segmentcount\":7,\"current\":true,\"hasdeletions\":true,\"directory\":\"org.apache.lucene.store.nrtcachingdirectory:nrtcachingdirectory(mmapdirectory@/opt/alfresco-search-services/solrhome/alfresco/index lockfactory=org.apache.lucene.store.nativefslockfactory@17aaa8c6; maxcachemb=48.0 maxmergesizemb=4.0)\",\"segmentsfile\":\"segments_16t\",\"segmentsfilesizeinbytes\":553,\"userdata\":{\"committimemsec\":\"1634259620015\"},\"lastmodified\":\"2021-10-15t01:00:20.015z\",\"sizeinbytes\":7442643,\"size\":\"7.1 mb\"}},\"archive\":{\"name\":\"archive\",\"instancedir\":\"/opt/alfresco-search-services/solrhome/archive\",\"datadir\":\"/opt/alfresco-search-services/solrhome//archive/\",\"config\":\"solrconfig.xml\",\"schema\":\"schema.xml\",\"starttime\":\"2021-08-19t02:12:04.556z\",\"uptime\":8396697416,\"index\":{\"numdocs\":4206,\"maxdoc\":4218,\"deleteddocs\":12,\"indexheapusagebytes\":-1,\"version\":7901,\"segmentcount\":6,\"current\":true,\"hasdeletions\":true,\"directory\":\"org.apache.lucene.store.nrtcachingdirectory:nrtcachingdirectory(mmapdirectory@/opt/alfresco-search-services/solrhome/archive/index lockfactory=org.apache.lucene.store.nativefslockfactory@17aaa8c6; maxcachemb=48.0 maxmergesizemb=4.0)\",\"segmentsfile\":\"segments_14m\",\"segmentsfilesizeinbytes\":489,\"userdata\":{\"committimemsec\":\"1634259610017\"},\"lastmodified\":\"2021-10-15t01:00:10.017z\",\"sizeinbytes\":801540,\"size\":\"782.75 kb\"}}}}"; // 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/