diff --git a/library/core/src/ops/function.rs b/library/core/src/ops/function.rs index 8d4b0a7ccacdb..11b43b621c7b8 100644 --- a/library/core/src/ops/function.rs +++ b/library/core/src/ops/function.rs @@ -576,9 +576,10 @@ mod impls { use crate::marker::Tuple; #[stable(feature = "rust1", since = "1.0.0")] - impl Fn for &F + #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] + impl const Fn for &F where - F: Fn, + F: ~const Fn, { extern "rust-call" fn call(&self, args: A) -> F::Output { (**self).call(args) @@ -586,9 +587,10 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl FnMut for &F + #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] + impl const FnMut for &F where - F: Fn, + F: ~const Fn, { extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output { (**self).call(args) @@ -596,9 +598,10 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl FnOnce for &F + #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] + impl const FnOnce for &F where - F: Fn, + F: ~const Fn, { type Output = F::Output; @@ -608,9 +611,10 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl FnMut for &mut F + #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] + impl const FnMut for &mut F where - F: FnMut, + F: ~const FnMut, { extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output { (*self).call_mut(args) @@ -618,9 +622,10 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl FnOnce for &mut F + #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] + impl const FnOnce for &mut F where - F: FnMut, + F: ~const FnMut, { type Output = F::Output; extern "rust-call" fn call_once(self, args: A) -> F::Output { diff --git a/src/test/ui/consts/fn_trait_refs.rs b/src/test/ui/consts/fn_trait_refs.rs new file mode 100644 index 0000000000000..bc8766c74c60f --- /dev/null +++ b/src/test/ui/consts/fn_trait_refs.rs @@ -0,0 +1,80 @@ +// build-pass + +#![feature(const_fn_trait_ref_impls)] +#![feature(fn_traits)] +#![feature(unboxed_closures)] +#![feature(const_trait_impl)] +#![feature(const_mut_refs)] +#![feature(const_cmp)] +#![feature(const_refs_to_cell)] + +use std::marker::Destruct; + +const fn tester_fn(f: T) -> T::Output +where + T: ~const Fn<()> + ~const Destruct, +{ + f() +} + +const fn tester_fn_mut(mut f: T) -> T::Output +where + T: ~const FnMut<()> + ~const Destruct, +{ + f() +} + +const fn tester_fn_once(f: T) -> T::Output +where + T: ~const FnOnce<()>, +{ + f() +} + +const fn test_fn(mut f: T) -> (T::Output, T::Output, T::Output) +where + T: ~const Fn<()> + ~const Destruct, +{ + ( + // impl const Fn for &F + tester_fn(&f), + // impl const FnMut for &F + tester_fn_mut(&f), + // impl const FnOnce for &F + tester_fn_once(&f), + ) +} + +const fn test_fn_mut(mut f: T) -> (T::Output, T::Output) +where + T: ~const FnMut<()> + ~const Destruct, +{ + ( + // impl const FnMut for &mut F + tester_fn_mut(&mut f), + // impl const FnOnce for &mut F + tester_fn_once(&mut f), + ) +} +const fn test(i: i32) -> i32 { + i + 1 +} + +const fn main() { + const fn one() -> i32 { + 1 + }; + const fn two() -> i32 { + 2 + }; + + // FIXME(const_cmp_tuple) + let test_one = test_fn(one); + assert!(test_one.0 == 1); + assert!(test_one.1 == 1); + assert!(test_one.2 == 1); + + let test_two = test_fn_mut(two); + assert!(test_two.0 == 1); + assert!(test_two.1 == 1); +}