rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Rollup merge of #88963 - fee1-dead:const-iterator, r=oli-obk

Browse Source 
Coerce const FnDefs to implement const Fn traits

You can now pass a FnDef to a function expecting `F` where `F: ~const FnTrait`.

r? ``@oli-obk``

``@rustbot`` label T-compiler F-const_trait_impl
This commit is contained in:
Manish Goregaokar
2021-10-01 14:46:48 -07:00
committed by GitHub
parent 2bab0a08e9 f8aa73d3dd
commit 743e842afb
11 changed files with 79 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
compiler/rustc_trait_selection/src/traits/select/mod.rs
View File

@@ -1112,6 +1112,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
// generator, this will raise error in other places
// or ignore error with const_async_blocks feature
GeneratorCandidate => {}
// FnDef where the function is const
FnPointerCandidate { is_const: true } => {}
ConstDropCandidate => {}
_ => {
// reject all other types of candidates
@@ -1539,6 +1541,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
}
}
// Drop otherwise equivalent non-const fn pointer candidates
(FnPointerCandidate { .. }, FnPointerCandidate { is_const: false }) => true,
// Global bounds from the where clause should be ignored
// here (see issue #50825). Otherwise, we have a where
// clause so don't go around looking for impls.
@@ -1549,7 +1554,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(..)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)
@@ -1567,7 +1572,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(_)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)
@@ -1597,7 +1602,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(..)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)
@@ -1609,7 +1614,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(..)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)
@@ -1690,7 +1695,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(_)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)
@@ -1699,7 +1704,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
ImplCandidate(_)
| ClosureCandidate
| GeneratorCandidate
| FnPointerCandidate
| FnPointerCandidate { .. }
| BuiltinObjectCandidate
| BuiltinUnsizeCandidate
| TraitUpcastingUnsizeCandidate(_)