I was working in coding dojo trying to learn Rust. In the attached link is all our code and test. However, we got stumped as to why we required calling clone() in one function but not the other.
Why do I need to call game.clone() on line 23 of lib.rs in this link https://cyber-dojo.org/kata/edit/WvEB5z
pub fn say_game_score(game: Game) -> String { if game.player1.score == game.player2.score { return say_equal_score(game.player1.score); } if can_be_won(game) { // This line required game.clone() WHY??? return say_winning_situation(game); // This line does NOT require game.clone() } return format!( "{} {}", say_score_name(game.player1.score), say_score_name(game.player2.score) ); } fn say_winning_situation(game: Game) -> String { if game.player1.score > game.player2.score { return say_leading_situation(game.player1.name, game.player1.score - game.player2.score); } else { return say_leading_situation(game.player2.name, game.player2.score - game.player1.score); } } fn can_be_won(game: Game) -> bool { return game.player1.score > FORTY || game.player2.score > FORTY; } 
