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// run-pass
#![allow(type_alias_bounds)]
#![feature(unsized_tuple_coercion)]
type Fat<T: ?Sized> = (isize, &'static str, T);
// x is a fat pointer
fn foo(x: &Fat<[isize]>) {
let y = &x.2;
assert_eq!(x.2.len(), 3);
assert_eq!(y[0], 1);
assert_eq!(x.2[1], 2);
assert_eq!(x.0, 5);
assert_eq!(x.1, "some str");
}
fn foo2<T:ToBar>(x: &Fat<[T]>) {
let y = &x.2;
let bar = Bar;
assert_eq!(x.2.len(), 3);
assert_eq!(y[0].to_bar(), bar);
assert_eq!(x.2[1].to_bar(), bar);
assert_eq!(x.0, 5);
assert_eq!(x.1, "some str");
}
fn foo3(x: &Fat<Fat<[isize]>>) {
let y = &(x.2).2;
assert_eq!(x.0, 5);
assert_eq!(x.1, "some str");
assert_eq!((x.2).0, 8);
assert_eq!((x.2).1, "deep str");
assert_eq!((x.2).2.len(), 3);
assert_eq!(y[0], 1);
assert_eq!((x.2).2[1], 2);
}
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
struct Bar;
trait ToBar {
fn to_bar(&self) -> Bar;
}
impl ToBar for Bar {
fn to_bar(&self) -> Bar {
*self
}
}
pub fn main() {
// With a vec of ints.
let f1 = (5, "some str", [1, 2, 3]);
foo(&f1);
let f2 = &f1;
foo(f2);
let f3: &Fat<[isize]> = f2;
foo(f3);
let f4: &Fat<[isize]> = &f1;
foo(f4);
let f5: &Fat<[isize]> = &(5, "some str", [1, 2, 3]);
foo(f5);
// With a vec of Bars.
let bar = Bar;
let f1 = (5, "some str", [bar, bar, bar]);
foo2(&f1);
let f2 = &f1;
foo2(f2);
let f3: &Fat<[Bar]> = f2;
foo2(f3);
let f4: &Fat<[Bar]> = &f1;
foo2(f4);
let f5: &Fat<[Bar]> = &(5, "some str", [bar, bar, bar]);
foo2(f5);
// Assignment.
let f5: &mut Fat<[isize]> = &mut (5, "some str", [1, 2, 3]);
f5.2[1] = 34;
assert_eq!(f5.2[0], 1);
assert_eq!(f5.2[1], 34);
assert_eq!(f5.2[2], 3);
// Zero size vec.
let f5: &Fat<[isize]> = &(5, "some str", []);
assert!(f5.2.is_empty());
let f5: &Fat<[Bar]> = &(5, "some str", []);
assert!(f5.2.is_empty());
// Deeply nested.
let f1 = (5, "some str", (8, "deep str", [1, 2, 3]));
foo3(&f1);
let f2 = &f1;
foo3(f2);
let f3: &Fat<Fat<[isize]>> = f2;
foo3(f3);
let f4: &Fat<Fat<[isize]>> = &f1;
foo3(f4);
let f5: &Fat<Fat<[isize]>> = &(5, "some str", (8, "deep str", [1, 2, 3]));
foo3(f5);
// Box.
let f1 = Box::new([1, 2, 3]);
assert_eq!((*f1)[1], 2);
let f2: Box<[isize]> = f1;
assert_eq!((*f2)[1], 2);
// Nested Box.
let f1 : Box<Fat<[isize; 3]>> = Box::new((5, "some str", [1, 2, 3]));
foo(&*f1);
let f2 : Box<Fat<[isize]>> = f1;
foo(&*f2);
let f3 : Box<Fat<[isize]>> =
Box::<Fat<[_; 3]>>::new((5, "some str", [1, 2, 3]));
foo(&*f3);
}
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