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"'Target.*Write MBps\n(?:[\w; %\.]+,){9}([\w; %\.]+)").unwrap(); let string = "'Test Type,Test Description,,,,,,,,,, 0,,,,,,,,,,, 'Version,,,,,,,,,,, 2006.07.27,,,,,,,,,,, 'Time Stamp,,,,,,,,,,, 2016-01-06 19:40:56:182,,,,,,,,,,, 'Test Type,Test Description,,,,,,,,,, 0,,,,,,,,,,, 'Version,,,,,,,,,,, 2006.07.27,,,,,,,,,,, 'Time Stamp,,,,,,,,,,, 2016-01-06 19:41:32:625,,,,,,,,,,, 'Test Type,Test Description,,,,,,,,,, 0,,,,,,,,,,, 'Version,,,,,,,,,,, 2006.07.27,,,,,,,,,,, 'Time Stamp,,,,,,,,,,, 2016-01-06 19:41:53:145,,,,,,,,,,, 'Test Type,Test Description,,,,,,,,,, 0,,,,,,,,,,, 'Version,,,,,,,,,,, 2006.07.27,,,,,,,,,,, 'Time Stamp,,,,,,,,,,, 2016-01-06 19:43:53:456,,,,,,,,,,, 'Access specifications,,,,,,,,,,, 'Access specification name,default assignment,,,,,,,,,, 512B; 100% Read; 0% random,0,,,,,,,,,, 'size,% of size,% reads,% random,delay,burst,align,reply,,,, 209715712,100,100,0,0,1,0,0,,,, 'End access specifications,,,,,,,,,,, 'Results,,,,,,,,,,, 'Target Type,Target Name,Access Specification Name,# Managers,# Workers,# Disks,IOps,Read IOps,Write IOps,MBps,Read MBps,Write MBps ALL,All,512B; 100% Read; 0% random,1,1,1,0.571416,0.571416,0,114.283511,114.283511,0 MANAGER,A01030016NB,512B; 100% Read; 0% random,,1,1,0.571416,0.571416,0,114.283511,114.283511,0 PROCESSOR,CPU 0,,,,,,,,,, PROCESSOR,CPU 1,,,,,,,,,, PROCESSOR,CPU 2,,,,,,,,,, PROCESSOR,CPU 3,,,,,,,,,, WORKER,Worker 1,512B; 100% Read; 0% random,,,1,0.571416,0.571416,0,114.283511,114.283511,0 DISK,F:新增磁碟區,,,,,0.571416,0.571416,0,114.283511,114.283511,0 'Time Stamp,,,,,,,,,,, 2016-01-06 19:44:21:973,,,,,,,,,,, 'Test Type,Test Description,,,,,,,,,, 0,,,,,,,,,,, 'Version,,,,,,,,,,, 2006.07.27,,,,,,,,,,, 'Time Stamp,,,,,,,,,,, 2016-01-06 19:45:17:785,,,,,,,,,,, 'Access specifications,,,,,,,,,,, 'Access specification name,default assignment,,,,,,,,,, 512B; 100% Read; 0% random,0,,,,,,,,,, 'size,% of size,% reads,% random,delay,burst,align,reply,,,, 102912,100,100,0,0,1,0,0,,,, 'End access specifications,,,,,,,,,,, 'Results,,,,,,,,,,, 'Target Type,Target Name,Access Specification Name,# Managers,# Workers,# Disks,IOps,Read IOps,Write IOps,MBps,Read MBps,Write MBps ALL,All,512B; 100% Read; 0% random,1,1,1,1216.250748,1216.250748,0,119.36836,119.36836,0 MANAGER,A01030016NB,512B; 100% Read; 0% random,,1,1,1216.250748,1216.250748,0,119.36836,119.36836,0 PROCESSOR,CPU 0,,,,,,,,,, PROCESSOR,CPU 1,,,,,,,,,, PROCESSOR,CPU 2,,,,,,,,,, PROCESSOR,CPU 3,,,,,,,,,, WORKER,Worker 1,512B; 100% Read; 0% random,,,1,1216.250748,1216.250748,0,119.36836,119.36836,0 DISK,F:新增磁碟區,,,,,1216.250748,1216.250748,0,119.36836,119.36836,0 'Time Stamp,,,,,,,,,,, 2016-01-06 19:45:30:673,,,,,,,,,,,"; // 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/