Regex for CSS Class Name

javascript

const regex = /^-?[_a-zA-Z][_a-zA-Z0-9-]*$/;
const isValid = regex.test(value);

python

import re
pattern = r'^-?[_a-zA-Z][_a-zA-Z0-9-]*$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^-?[_a-zA-Z][_a-zA-Z0-9-]*$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^-?[_a-zA-Z][_a-zA-Z0-9-]*$/', $value)) {
    echo "valid";
}

java

String pattern = "^-?[_a-zA-Z][_a-zA-Z0-9-]*$";
boolean isValid = value.matches(pattern);