36 lines
959 B
Rust
36 lines
959 B
Rust
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#![feature(dyn_star)] //~ WARNING the feature `dyn_star` is incomplete
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use std::future::Future;
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pub fn dyn_func<T>(
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executor: impl FnOnce(T) -> dyn Future<Output = ()>,
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) -> Box<dyn FnOnce(T) -> dyn Future<Output = ()>> {
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Box::new(executor) //~ ERROR may not live long enough
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}
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pub fn dyn_star_func<T>(
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executor: impl FnOnce(T) -> dyn* Future<Output = ()>,
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) -> Box<dyn FnOnce(T) -> dyn* Future<Output = ()>> {
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Box::new(executor) //~ ERROR may not live long enough
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}
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trait Trait {
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fn method(&self) {}
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}
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impl Trait for fn() {}
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pub fn in_ty_param<T: Fn() -> dyn std::fmt::Debug> (t: T) {
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t.method();
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//~^ ERROR no method named `method` found for type parameter `T`
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}
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fn with_sized<T: Fn() -> &'static (dyn std::fmt::Debug) + ?Sized>() {
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without_sized::<T>();
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//~^ ERROR the size for values of type `T` cannot be known at compilation time
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}
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fn without_sized<T: Fn() -> &'static dyn std::fmt::Debug>() {}
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fn main() {}
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