Test, validate and match regular expressions
Matches one or more consecutive characters that are NOT English letters, including digits, spaces, punctuation, and symbols. The negated character class [^a-zA-Z] excludes both lowercase and uppercase alphabets. With the global flag, it finds all such sequences in a string. Commonly used to detect, strip, or remove non-alphabetic characters, validate letter-only input, or split text by non-letter delimiters.