dave on Nostr: fn common_char_functional<'a>(str1: &'a str, str2: &'a str) -> &'a str { str1.chars() ...

fn common_char_functional<'a>(str1: &'a str, str2: &'a str) -> &'a str {
str1.chars()
.filter(|ch1| str2.contains(*ch1))
.collect::<String>()
.trim_start_matches('L')
}