mirror of https://github.com/rust-lang/rust
24 lines
536 B
Rust
24 lines
536 B
Rust
#![feature(type_alias_impl_trait)]
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//@ build-pass
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trait Bar {
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fn bar(&self);
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}
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type FooFn<B> = impl FnOnce(B);
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fn foo<B: Bar>() -> FooFn<B> {
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fn mop<B: Bar>(bar: B) { bar.bar() }
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mop as fn(B)
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// function pointers don't have any obligations on them,
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// thus the above compiles. It's obviously unsound to just
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// procure a `FooFn` from the ether without making sure that
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// the pointer is actually legal for all `B`
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}
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fn main() {
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let boom: FooFn<u32> = unsafe { core::mem::zeroed() };
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boom(42);
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}
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