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
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression


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)^<(?i)(?:input|textarea|\\w{0,}TextBox|\\w{0,}Field).*(?:name|id)=(?:\"|\')\w+(?:\"|\').*"#).unwrap(); let string = "{{! my-form.hbs }} <form onsubmit={{action \"submit\"}}> <label for=\"name\">Name:</label> <input type=\"text\" id=\"name\" value={{}}> <label for=\"email\">Email:</label> <input type=\"email\" id=\"email\" value={{}}> <label for=\"message\">Message:</label> <textarea id=\"message\">{{model.message}}</textarea> <button type=\"submit\">Submit</button> </form> <html> <head> <title>My Form</title> </head> <body> <form> <label for=\"name\">Name:</label> <input type=\"text\" name=\"name\" id=\"name\"/> <label for=\"email\">Email:</label> <input type=\"email\" name=\"email\" id=\"email\"/> <label for=\"message\">Message:</label> <textarea name=\"message\" id=\"message\"></textarea> <button type=\"button\" onclick=\"submitForm()\">Submit</button> </form> </body> </html>"; // 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: