fn main() { let u = 5 as bool; //~ ERROR cannot cast `i32` as `bool` //~| HELP compare with zero instead //~| SUGGESTION != 0 let t = (1 + 2) as bool; //~ ERROR cannot cast `i32` as `bool` //~| HELP compare with zero instead //~| SUGGESTION != 0 let _ = 5_u32 as bool; //~ ERROR cannot cast `u32` as `bool` //~| HELP compare with zero instead let _ = 64.0_f64 as bool; //~ ERROR cannot cast `f64` as `bool` //~| HELP compare with zero instead // Enums that can normally be cast to integers can't be cast to `bool`, just like integers. // Note that enums that cannot be cast to integers can't be cast to anything at *all* // so that's not tested here. enum IntEnum { Zero, One, Two } let _ = IntEnum::One as bool; //~ ERROR cannot cast `IntEnum` as `bool` fn uwu(_: u8) -> String { todo!() } unsafe fn owo() {} // fn item to bool let _ = uwu as bool; //~ ERROR cannot cast `fn(u8) -> String {uwu}` as `bool` // unsafe fn item let _ = owo as bool; //~ ERROR cannot cast `unsafe fn() {owo}` as `bool` // fn ptr to bool let _ = uwu as fn(u8) -> String as bool; //~ ERROR cannot cast `fn(u8) -> String` as `bool` let _ = 'x' as bool; //~ ERROR cannot cast `char` as `bool` let ptr = 1 as *const (); let _ = ptr as bool; //~ ERROR cannot cast `*const ()` as `bool` let v = "hello" as bool; //~^ ERROR casting `&'static str` as `bool` is invalid //~| HELP consider using the `is_empty` method on `&'static str` to determine if it contains anything }