rustHow to check if a regex is valid in Rust?

To check if a regex is valid in Rust, you can use the is_match method from the regex crate. This method takes a string and a regular expression as parameters and returns a boolean value indicating whether the string matches the regular expression.

Example code

use regex::Regex;

let re = Regex::new(r"^\d{4}-\d{2}-\d{2}$").unwrap();
let is_valid = re.is_match("2020-01-01");

println!("{}", is_valid);

Output example

true

Code explanation

• use regex::Regex;: imports the Regex type from the regex crate.
• let re = Regex::new(r"^\d{4}-\d{2}-\d{2}$").unwrap();: creates a new Regex object from the given regular expression. The unwrap method is used to convert the Result type returned by Regex::new into a Regex object.
• let is_valid = re.is_match("2020-01-01");: calls the is_match method on the Regex object, passing in a string to check against the regular expression.
• println!("{}", is_valid);: prints the boolean value returned by is_match.

Helpful links

• Regex documentation

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