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// run-pass
// This test relies on `TryFrom` being blanket impl for all `T: Into`
// and `TryInto` being blanket impl for all `U: TryFrom`
// This test was added to show the motivation for doing this
// over `TryFrom` being blanket impl for all `T: From`
#![feature(never_type)]
use std::convert::{TryInto, Infallible};
struct Foo<T> {
t: T,
}
// This fails to compile due to coherence restrictions
// as of Rust version 1.32.x, therefore it could not be used
// instead of the `Into` version of the impl, and serves as
// motivation for a blanket impl for all `T: Into`, instead
// of a blanket impl for all `T: From`
/*
impl<T> From<Foo<T>> for Box<T> {
fn from(foo: Foo<T>) -> Box<T> {
Box::new(foo.t)
}
}
*/
impl<T> Into<Vec<T>> for Foo<T> {
fn into(self) -> Vec<T> {
vec![self.t]
}
}
pub fn main() {
let _: Result<Vec<i32>, Infallible> = Foo { t: 10 }.try_into();
}
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