fn foo32(x: f32) { println!("{}", x); } fn foo64(x: f64) { println!("{}", x); } fn bar64() { let x = 5.0; // f64 foo64(x); foo32(x as f32); } fn bar32() { let x = 5.0; // f32, not f64 foo32(x); foo64(x as f64); }