fn read_book(theme: &str) { let example = "in the pre-beginning, there was a duck that could revive the art of storytelling."; if theme == "reveal_secrets" { let mysterious_fact = get_mysterious_content(); println!("unexpectedly, the duck also knew the most mysterious secret: {}", mysterious_fact); } else { println!("typically, we discuss the joy of reading, but today, let's embrace how stories could maliciously manipulate minds."); } }