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

/
/
si

Test String

Code Generator

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#"(?si)name\s+?z155e4d1dde106c_point_test.+?(?<!meta)data\s*".+?from\s+([^\s]+?)""#).unwrap(); let string = "MAP CONFIG \"MS_ERRORFILE\" \"/srv/mapservices/mapfiles/tmp/155e4d1dde106c.log\" DEBUG 5 IMAGETYPE PNG SIZE 1600 800 STATUS ON WEB METADATA \"wms_title\" \"Generated_Mapfile\" \"wms_onlineresource\" \"http://142.207.151.5/cgi-bin/mapserv?map=/srv/portal/www/Mapservices/mapfiles/TSAZones.map&version=1.0.0&service=wms\" \"wms_srs\" \"EPSG:3005 EPSG:4269 EPSG:3857\" \"wms_enable_request\" \"*\" \"wms_feature_info_mime_type\" \"text/html\" END QUERYFORMAT text/html END PROJECTION \"init=epsg:3005\" END OUTPUTFORMAT NAME png DRIVER AGG/PNG MIMETYPE \"image/png\" IMAGEMODE RGBA EXTENSION \"png\" FORMATOPTION \"GAMMA=0.75\" TRANSPARENT ON END LAYER DEBUG 5 NAME z155e4d1dde106c_point_test DUMP TRUE TEMPLATE \"querytemplate.html\" PROJECTION \"init=epsg:3005\" END METADATA \"wms_srs\" \"EPSG:3005\" \"title\" \"TSA Zones\" \"wms_title\" \"TSA Zones\" \"wms_include_items\" \"all\" \"gml_include_items\" \"all\" END TYPE POINT CONNECTIONTYPE POSTGIS CONNECTION \"host=127.0.0.1 dbname=stewardship user=portal_readwrite password=portal_readwrite\" DATA \"wkb_geometry from z155e4d1dde106c_point_test\" CLASS STYLE COLOR 59 189 57 OUTLINECOLOR 147 155 48 OPACITY 100 END END END LAYER DEBUG 5 NAME z155e4d1dde106c_poly_test1 DUMP TRUE TEMPLATE \"querytemplate.html\" PROJECTION \"init=epsg:3005\" END METADATA \"wms_srs\" \"EPSG:3005\" \"title\" \"TSA Zones\" \"wms_title\" \"TSA Zones\" \"wms_include_items\" \"all\" \"gml_include_items\" \"all\" END TYPE POLYGON CONNECTIONTYPE POSTGIS CONNECTION \"host=127.0.0.1 dbname=stewardship user=portal_readwrite password=portal_readwrite\" DATA \"wkb_geometry from z155e4d1dde106c_poly_test1\" CLASS STYLE COLOR 121 71 143 OUTLINECOLOR 96 133 94 OPACITY 100 END END END END"; // 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/