mirror of https://github.com/rust-lang/rust
55 lines
1.1 KiB
Rust
55 lines
1.1 KiB
Rust
//@ check-pass
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#![allow(dead_code)]
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trait Structure<E>: Sized where E: Encoding {
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type RefTarget: ?Sized;
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type FfiPtr;
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unsafe fn borrow_from_ffi_ptr<'a>(ptr: Self::FfiPtr) -> Option<&'a Self::RefTarget>;
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}
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enum Slice {}
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impl<E> Structure<E> for Slice where E: Encoding {
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type RefTarget = [E::Unit];
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type FfiPtr = (*const E::FfiUnit, usize);
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unsafe fn borrow_from_ffi_ptr<'a>(_ptr: Self::FfiPtr) -> Option<&'a Self::RefTarget> {
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panic!()
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}
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}
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trait Encoding {
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type Unit: Unit;
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type FfiUnit;
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}
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trait Unit {}
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enum Utf16 {}
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impl Encoding for Utf16 {
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type Unit = Utf16Unit;
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type FfiUnit = u16;
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}
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struct Utf16Unit(pub u16);
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impl Unit for Utf16Unit {}
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type SUtf16Str = SeStr<Slice, Utf16>;
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struct SeStr<S, E> where S: Structure<E>, E: Encoding {
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_data: S::RefTarget,
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}
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impl<S, E> SeStr<S, E> where S: Structure<E>, E: Encoding {
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pub unsafe fn from_ptr<'a>(_ptr: S::FfiPtr) -> Option<&'a Self> {
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panic!()
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}
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}
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fn main() {
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const TEXT_U16: &'static [u16] = &[];
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let _ = unsafe { SUtf16Str::from_ptr((TEXT_U16.as_ptr(), TEXT_U16.len())).unwrap() };
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}
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