Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

r"
"
gm

Test String

Substitution

Processing...

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)([0-9A-f]{2}[:-]){5}[0-9A-f]{2}").unwrap(); let string = "1031AP9 2 AIR-CAP3502I-A-K9 2c:54:2d:0a:1a:1e default location US 10.10.131.108 0 [0 ,0 ,0 ] 1031AP4 2 AIR-CAP3502I-A-K9 2c:54:2d:0d:d6:d0 default location US 10.10.131.94 1 [0 ,0 ,0 ] 1031AP5 2 AIR-CAP3502I-A-K9 2c:54:2d:13:04:d5 default location US 10.10.131.107 6 [0 ,0 ,0 ] 1031AP11 2 AIR-CAP3702I-B-K9 a0:e0:af:6a:80:a4 default location US 10.10.131.106 1 [0 ,0 ,0 ] 1031AP6 2 AIR-CAP3502I-A-K9 2c:54:2d:13:05:24 default location US 10.10.131.101 1 [0 ,0 ,0 ] 1031AP2 2 AIR-CAP3502I-A-K9 2c:54:2d:0a:1b:f4 default location US 10.10.131.109 0 [0 ,0 ,0 ] 1031AP3 2 AIR-CAP3502I-A-K9 2c:54:2d:0a:1a:c6 default location US 10.10.131.104 0 [0 ,0 ,0 ] 1031AP8 2 AIR-CAP3702I-B-K9 d4:c9:3c:9d:4a:f4 default location US 10.10.131.114 3 [0 ,0 ,0 ] 1031AP1 2 AIR-CAP3502I-A-K9 2c:54:2d:0d:d7:11 default location US 10.10.131.105 3 [0 ,0 ,0 ] 1031AP7 2 AIR-CAP3502I-A-K9 2c:54:2d:0a:1c:21 default location US 10.10.131.93 0 [0 ,0 ,0 ] 1031AP10 2 AIR-CAP3502I-A-K9 2c:54:2d:13:02:53 default location US 10.10.131.103 0 [0 ,0 ,0 ]"; let substitution = " "; // result will be a String with the substituted value let result = regex.replace_all(string, substitution); println!("{}", result); }

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/