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

/
/
mg

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"(?m)^\s*(\w*)=\s?\d").unwrap(); let string = "#!/bin/bash flavor=${1:-dzen2} function gmail() { while true do inbox_count=$(wget -q -O- --auth-no-challenge --user=something@gmail.com --password=something 'https://mail.goog$ echo \"Gg:$inbox_count\" sleep 60 done } function weather() { while true do weather_stat=$($HOME/.config/i3/./weather.sh) echo \"F$weather_stat\" sleep 900 done } function time_date() { while true do klocka=$(date +'%A den %d %B v%V %H:%M') echo \"S$klocka\" sleep 10 done < <(echo) } bspc control --put-status xtitle -sf \"T%s\" > \"$PANEL_FIFO\" & weather > \"$PANEL_FIFO\" & gmail > \"$PANEL_FIFO\" & time_date > \"$PANEL_FIFO\" & case \"$flavor\" in bar) cat \"$PANEL_FIFO\" | .config/bspwm/panel_bar | bar ;; dzen2) . .config/bspwm/panel_colors PANEL_HEIGHT=14 FONT_FAMILY='Dejavu Sans' FONT_SIZE=9 cat \"$PANEL_FIFO\" | .config/bspwm/panel_dzen2 -f \"$FONT_FAMILY\" -s \"$FONT_SIZE\" | \\ dzen2 -h $PANEL_HEIGHT -dock -ta l -title-name panel -fn \"${FONT_FAMILY}:pixelsize=${FONT_SIZE}\" \\ -fg \"$COLOR_FOREGROUND\" -bg \"$COLOR_BACKGROUND\" ;; esac"; // 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/