fn take(_f: impl FnMut(i32)) {} fn test1(f: impl FnMut(u32)) { take(f) //~^ ERROR [E0277] } fn test2(f: impl FnMut(i32, i32)) { take(f) //~^ ERROR [E0277] } fn test3(f: impl FnMut()) { take(f) //~^ ERROR [E0277] } fn test4(f: impl FnOnce(i32)) { take(f) //~^ ERROR [E0277] } fn test5(f: impl FnOnce(u32)) { take(f) //~^ ERROR [E0277] } fn main() {}