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
No Match

/
/
Ui

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"(?Ui)([a-z\-_0-9\/\:\.]*\.(jpg|jpeg|png|gif))").unwrap(); let string = "<a style=\"display:block;\" href=\"javascript:void(0);\" onclick=\"expandImageRotate ( 'xImage_56362441','http://snpi.dell.com/snp/images/products/large/en-th~370-ACMK/370-ACMK.jpg',event,this,'' );\"><img id=\"xImage_56362441_sm_Image\" border=\"0\" alt=\"Dell 8 GB Certified Replacement Memory Module for Select Dell Systems- UDIMM ECC\" title=\"Dell 8 GB Certified Replacement Memory Module for Select Dell Systems- UDIMM ECC\" width=\"200\" src=\"http://snpi.dell.com/snp/images/products/mlrg/en-th~370-ACMK/370-ACMK.jpg\" z></a> </span></td></tr> <tr><td colspan=\"2\" style=\"padding: 15px 0px 5px 0px\"><table cellpadding=\"4\" cellspacing=\"0\" align=\"center\" border=\"0\"><tr class=\"thumbnailRow\"><td align=\"center\"><table cellpadding=\"0\" cellspacing=\"0\" border=\"0\"> <tr> <td><img src=\"http://i.dell.com/images/global/brand/ui/top_left_small.gif\" width=\"3\" height=\"3\"></td> <td width=\"100%\"><img src=\"http://i.dell.com/images/global/brand/ui/top_horiz_small.gif\" width=\"100%\" height=\"3\" border=\"0\"></td> <td class=\"rightAlign\"><img src=\"http://i.dell.com/images/global/brand/ui/top_right_small.gif\" width=\"3\" height=\"3\"></td> </tr> <tr> <td class=\"leftVertSmall\"></td> <td><span style=\"display:inline-block;width:40px;\"> <script type=\"text/javascript\"> RegisterImage('original_image', 'http://snpi.dell.com/snp/images/products/mlrg/en-th~370-ACMK/370-ACMK.jpg', 'http://snpi.dell.com/snp/images/products/large/en-th~370-ACMK/370-ACMK.jpg', \"Dell 8 GB Certified Replacement Memory Module for Select Dell Systems- UDIMM ECC\", 'xImage_18637405', ''); </script><div style=\"position: absolute; top: 0pt; left: 0pt;\" id=\"xImage_18637405_container\"></div>"; // 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/