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// run-pass
struct Foo<A = (isize, char)> {
a: A
}
impl Foo<isize> {
fn bar_int(&self) -> isize {
self.a
}
}
impl Foo<char> {
fn bar_char(&self) -> char {
self.a
}
}
impl Foo {
fn bar(&self) {
let (i, c): (isize, char) = self.a;
assert_eq!(Foo { a: i }.bar_int(), i);
assert_eq!(Foo { a: c }.bar_char(), c);
}
}
impl<A: Clone> Foo<A> {
fn baz(&self) -> A {
self.a.clone()
}
}
fn default_foo(x: Foo) {
let (i, c): (isize, char) = x.a;
assert_eq!(i, 1);
assert_eq!(c, 'a');
x.bar();
assert_eq!(x.baz(), (1, 'a'));
}
#[derive(PartialEq, Debug)]
struct BazHelper<T>(T);
#[derive(PartialEq, Debug)]
// Ensure that we can use previous type parameters in defaults.
struct Baz<T, U = BazHelper<T>, V = Option<U>>(T, U, V);
fn main() {
default_foo(Foo { a: (1, 'a') });
let x: Baz<bool> = Baz(true, BazHelper(false), Some(BazHelper(true)));
assert_eq!(x, Baz(true, BazHelper(false), Some(BazHelper(true))));
}
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