scrabble finder

main.rs

const WORDS: &str = include_str!("../words.txt");

fn main() {
  let pattern = std::env::args()
                .nth(1)
                .expect("usage: words <pattern> [known letters]")
                .to_ascii_lowercase()
                .replace(" ", "")
                ;

  let known = std::env::args()
                .skip(1)
                .map(|s| s.chars().filter(|&c| c != '?' && c != '_' && !c.is_whitespace()).collect::<String>())
                .collect::<Vec<_>>()
                ;
  let known: String = known.join("").to_ascii_lowercase();
  eprintln!("known letters: {:?}", known);

  let mut res = Vec::new();

  'O: for word in WORDS.lines() {
    if word.len() == pattern.len() {
      // "?a??ern"
      let letters = word.as_bytes();
      let pattern = pattern.as_bytes();
      let known = known.as_bytes();
      for i in 0..letters.len() {
        let p = pattern[i];
        let w = letters[i].to_ascii_lowercase();
        if p == b'?' || p == b'_' {
          // the masked letter should not by one of the present letters
          if known.iter().any(|&c| c == w) {
            continue 'O;
          }
        } else if p != w {
          continue 'O;
        }
      }
      res.push(word);
    }
  }

  eprintln!("{} results for {:?} among {} words", res.len(), pattern, WORDS.lines().count());
  for w in res.iter().take(20) {
    println!("{}", w);
  }
}