diff --git a/library/core/src/convert/mod.rs b/library/core/src/convert/mod.rs index 1e512af48051e..72dbe845c97a9 100644 --- a/library/core/src/convert/mod.rs +++ b/library/core/src/convert/mod.rs @@ -532,9 +532,10 @@ where // From implies Into #[stable(feature = "rust1", since = "1.0.0")] -impl Into for T +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl const Into for T where - U: From, + U: ~const From, { fn into(self) -> U { U::from(self) @@ -543,7 +544,8 @@ where // From (and thus Into) is reflexive #[stable(feature = "rust1", since = "1.0.0")] -impl From for T { +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl const From for T { fn from(t: T) -> T { t } diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs index 265ba9f1bb91b..9c4429d320f1f 100644 --- a/library/core/src/lib.rs +++ b/library/core/src/lib.rs @@ -82,6 +82,7 @@ #![feature(const_float_bits_conv)] #![feature(const_float_classify)] #![feature(const_heap)] +#![feature(const_convert)] #![feature(const_inherent_unchecked_arith)] #![feature(const_int_unchecked_arith)] #![feature(const_intrinsic_copy)] diff --git a/library/core/src/option.rs b/library/core/src/option.rs index 94d892dd787a6..a162c0340fb24 100644 --- a/library/core/src/option.rs +++ b/library/core/src/option.rs @@ -2019,7 +2019,8 @@ impl> FromIterator> for Option { } #[unstable(feature = "try_trait_v2", issue = "84277")] -impl ops::Try for Option { +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl const ops::Try for Option { type Output = T; type Residual = Option; @@ -2038,7 +2039,8 @@ impl ops::Try for Option { } #[unstable(feature = "try_trait_v2", issue = "84277")] -impl ops::FromResidual for Option { +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl const ops::FromResidual for Option { #[inline] fn from_residual(residual: Option) -> Self { match residual { diff --git a/library/core/src/result.rs b/library/core/src/result.rs index 4a300f857e9ed..bd4e623732e2a 100644 --- a/library/core/src/result.rs +++ b/library/core/src/result.rs @@ -1889,7 +1889,8 @@ impl> FromIterator> for Result { } #[unstable(feature = "try_trait_v2", issue = "84277")] -impl ops::Try for Result { +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl const ops::Try for Result { type Output = T; type Residual = Result; @@ -1908,7 +1909,10 @@ impl ops::Try for Result { } #[unstable(feature = "try_trait_v2", issue = "84277")] -impl> ops::FromResidual> for Result { +#[rustc_const_unstable(feature = "const_convert", issue = "88674")] +impl> const ops::FromResidual> + for Result +{ #[inline] fn from_residual(residual: Result) -> Self { match residual { diff --git a/library/core/tests/convert.rs b/library/core/tests/convert.rs new file mode 100644 index 0000000000000..f1048f4cf09cb --- /dev/null +++ b/library/core/tests/convert.rs @@ -0,0 +1,16 @@ +#[test] +fn convert() { + const fn from(x: i32) -> i32 { + i32::from(x) + } + + const FOO: i32 = from(42); + assert_eq!(FOO, 42); + + const fn into(x: Vec) -> Vec { + x.into() + } + + const BAR: Vec = into(Vec::new()); + assert_eq!(BAR, Vec::::new()); +} diff --git a/library/core/tests/lib.rs b/library/core/tests/lib.rs index cd3aed4cd28f8..f25106abc8821 100644 --- a/library/core/tests/lib.rs +++ b/library/core/tests/lib.rs @@ -9,12 +9,13 @@ #![feature(cfg_target_has_atomic)] #![feature(const_assume)] #![feature(const_cell_into_inner)] +#![feature(const_convert)] #![feature(const_maybe_uninit_assume_init)] +#![feature(const_num_from_num)] #![feature(const_ptr_read)] #![feature(const_ptr_write)] #![feature(const_ptr_offset)] #![feature(const_trait_impl)] -#![feature(const_num_from_num)] #![feature(core_intrinsics)] #![feature(core_private_bignum)] #![feature(core_private_diy_float)] @@ -83,6 +84,7 @@ mod char; mod clone; mod cmp; mod const_ptr; +mod convert; mod fmt; mod hash; mod intrinsics; diff --git a/src/test/ui/consts/try-operator.rs b/src/test/ui/consts/try-operator.rs new file mode 100644 index 0000000000000..fe43b132cbd7f --- /dev/null +++ b/src/test/ui/consts/try-operator.rs @@ -0,0 +1,23 @@ +// run-pass + +#![feature(try_trait_v2)] +#![feature(const_trait_impl)] +#![feature(const_try)] +#![feature(const_convert)] + +fn main() { + const fn result() -> Result { + Err(())?; + Ok(true) + } + + const FOO: Result = result(); + assert_eq!(Err(()), FOO); + + const fn option() -> Option<()> { + None?; + Some(()) + } + const BAR: Option<()> = option(); + assert_eq!(None, BAR); +}