mirror of https://github.com/rust-lang/rust
21 lines
427 B
Rust
21 lines
427 B
Rust
// Check that parenthetical notation is feature-gated except with the
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// `Fn` traits.
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use std::marker;
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trait Foo<A> {
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type Output;
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fn dummy(&self, a: A) { }
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}
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fn main() {
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let x: Box<dyn Foo(isize)>;
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//~^ ERROR parenthetical notation is only stable when used with `Fn`-family
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// No errors with these:
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let x: Box<dyn Fn(isize)>;
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let x: Box<dyn FnMut(isize)>;
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let x: Box<dyn FnOnce(isize)>;
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}
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