The current help message is too much about "normal" macros to be used
as general message. Keep it for normal macros, and add custom help and
error messages for macro definitions.
Add note when item accessed from module via `m.i` rather than `m::i`.
(I tried to make this somewhat future-proofed, in that the `UnresolvedNameContext` could be expanded in the future with other cases besides paths that are known to be modules.)
This supersedes PR #30356 ; since I'm responsible for a bunch of new code here, someone else should review it. :)
This PR is a rebase of the original PR by @eddyb https://github.com/rust-lang/rust/pull/21836 with some unrebasable parts manually reapplied, feature gate added + type equality restriction added as described below.
This implementation is partial because the type equality restriction is applied to all type ascription expressions and not only those in lvalue contexts. Thus, all difficulties with detection of these contexts and translation of coercions having effect in runtime are avoided.
So, you can't write things with coercions like `let slice = &[1, 2, 3]: &[u8];`. It obviously makes type ascription less useful than it should be, but it's still much more useful than not having type ascription at all.
In particular, things like `let v = something.iter().collect(): Vec<_>;` and `let u = t.into(): U;` work as expected and I'm pretty happy with these improvements alone.
Part of https://github.com/rust-lang/rust/issues/23416
Make RFC 1214 warnings into errors, and rip out the "warn or err"
associated machinery. Future such attempts should go through lints
anyhow.
There is a fair amount of fallout in the compile-fail tests, as WF
checking now occurs earlier in the process.
r? @arielb1
associated machinery. Future such attempts should go through lints
anyhow.
There is a fair amount of fallout in the compile-fail tests, as WF
checking now occurs earlier in the process.
previously the error was erased and a `non-const path` error was emitted at the location of the field access instead of at the overflow location (as can be seen in the playground: http://is.gd/EuAF5F )
Ensure borrows of fn/closure params do not outlive invocations.
Does this by adding a new CallSiteScope to the region (or rather code extent) hierarchy, which outlives even the ParameterScope (which in turn outlives the DestructionScope of a fn/closure's body).
Fix#29793
r? @nikomatsakis
Currently, a coherence error based on overlapping impls simply mentions
the trait, and points to the two conflicting impls:
```
error: conflicting implementations for trait `Foo`
```
With this commit, the error will include all input types to the
trait (including the `Self` type) after unification between the
overlapping impls. In other words, the error message will provide
feedback with full type details, like:
```
error: conflicting implementations of trait `Foo<u32>` for type `u8`:
```
When the `Self` type for the two impls unify to an inference variable,
it is elided in the output, since "for type `_`" is just noise in that
case.
Closes#23980
r? @nikomatsakis
Currently, a coherence error based on overlapping impls simply mentions
the trait, and points to the two conflicting impls:
```
error: conflicting implementations for trait `Foo`
```
With this commit, the error will include all input types to the
trait (including the `Self` type) after unification between the
overlapping impls. In other words, the error message will provide
feedback with full type details, like:
```
error: conflicting implementations of trait `Foo<u32>` for type `u8`:
```
When the `Self` type for the two impls unify to an inference variable,
it is elided in the output, since "for type `_`" is just noise in that
case.
Closes#23980
We can now handle name resolution errors and get past type checking (if we're a bit lucky). This is the first step towards doing code completion for partial programs (we need error recovery in the parser and early access to save-analysis).
Closes https://github.com/rust-lang/rust/issues/29935
The attributes `deprecated` and `rustc_deprecated` are completely independent in this implementation and it leads to some noticeable code duplication. Representing `deprecated` as
```
Stability {
level: Stable { since: "" },
feature: "",
depr: Some(Deprecation),
}
```
or, contrariwise, splitting rustc_deprecation from stability makes most of the duplication go away.
I can do this refactoring, but before doing it I must be sure, that further divergence of `deprecated` and `rustc_deprecated` is certainly not a goal.
cc @llogiq
This PR for #30299 adds the name of the type where the field is missing.
The span that's used for the error seems correct. What may be confusing is when the initializer with the missing field contains other intializers. These are then included in the span. For example, consider the following listing.
struct A {
a1: i32,
a2: B,
}
struct B {
b1: i32,
b2: i32
}
fn main() {
let x = A {
a2: B {
b1: 1,
b2: 1
},
};
}
It will display the following code snippet along with the message that field `a2` is missing:
let x = A {
a2: B {
b1: 1,
b2: 1
},
};
By adding the name of the type it's clearer where the field is missing.
This fixes a bug in which the visibility of a use declaration defining a name in one namespace (e.g. the value namespace) is overridden by a later use declaration defining the same name in the other namespace (e.g. the type namespace). For example,
```rust
fn f() {}
pub mod bar {}
mod foo {
use f; // This import should not be visible outside `foo`,
pub use bar as f; // but it visible outside of `foo` because of this import.
}
fn main() { foo::f(); }
```
As the example demonstrates, this is a [breaking-change], but it looks unlikely to cause breakage in practice, and any breakage can be fixed by correcting visibility modifiers.
