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