use std::fmt; | |
fn foo() -> Box<impl fmt::Debug+?Sized> { | |
let x : Box<[u8]> = Box::new([0]); | |
x | |
} | |
fn bar() -> Box<impl fmt::Debug+?Sized> { | |
let y: Box<dyn fmt::Debug> = Box::new([0]); | |
y | |
} | |
fn main() { | |
let f = foo(); | |
let b = bar(); | |
// this is an `*mut [u8]` in practice | |
let f_raw : *mut _ = Box::into_raw(f); | |
// this is an `*mut fmt::Debug` in practice | |
let mut b_raw = Box::into_raw(b); | |
// ... and they should not be mixable | |
b_raw = f_raw as *mut _; //~ ERROR is invalid | |
} |