mirror of https://github.com/rust-lang/rust
17 lines
324 B
Rust
17 lines
324 B
Rust
//@ run-pass
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struct A<F: FnOnce()->T,T>(F::Output);
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struct B<F: FnOnce()->T,T>(A<F,T>);
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// Removing Option causes it to compile.
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fn foo<T,F: FnOnce()->T>(f: F) -> Option<B<F,T>> {
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Some(B(A(f())))
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}
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fn main() {
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let v = (|| foo(||4))();
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match v {
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Some(B(A(4))) => {},
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_ => unreachable!()
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}
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}
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