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// It should not be possible to use the concrete value of a defaulted
// associated type in the impl defining it -- otherwise, what happens
// if it's overridden?
#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
trait Example {
type Output;
fn generate(self) -> Self::Output;
}
impl<T> Example for T {
default type Output = Box<T>;
default fn generate(self) -> Self::Output {
Box::new(self) //~ ERROR mismatched types
}
}
impl Example for bool {
type Output = bool;
fn generate(self) -> bool { self }
}
fn trouble<T>(t: T) -> Box<T> {
Example::generate(t) //~ ERROR mismatched types
}
fn weaponize() -> bool {
let b: Box<bool> = trouble(true);
*b
}
fn main() {
weaponize();
}
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