From dc0db358abe19481e475e10c32149b53370f1a1c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 30 May 2024 05:57:31 +0200 Subject: Merging upstream version 1.72.1+dfsg1. Signed-off-by: Daniel Baumann --- .../non-const-default-const-specialized.rs | 39 ++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 tests/ui/rfcs/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs (limited to 'tests/ui/rfcs/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs') diff --git a/tests/ui/rfcs/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs b/tests/ui/rfcs/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs new file mode 100644 index 000000000..35aa52fbd --- /dev/null +++ b/tests/ui/rfcs/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs @@ -0,0 +1,39 @@ +// Tests that a non-const default impl can be specialized by a const trait impl, +// but that the default impl cannot be used in a const context. + +// run-pass + +#![feature(const_trait_impl)] +#![feature(min_specialization)] + +#[const_trait] +trait Value { + fn value() -> u32; +} + +const fn get_value() -> u32 { + T::value() +} + +impl Value for T { + default fn value() -> u32 { + println!("You can't do that (constly)"); + 0 + } +} + +struct FortyTwo; + +impl const Value for FortyTwo { + fn value() -> u32 { + 42 + } +} + +fn main() { + let zero = get_value::<()>(); + assert_eq!(zero, 0); + + const FORTY_TWO: u32 = get_value::(); + assert_eq!(FORTY_TWO, 42); +} -- cgit v1.2.3