When reporting "consider removing this semicolon" hint message, the
offending semicolon may come from macro call site instead of macro
itself. Using the more appropriate span makes the hint more helpful.
Closes#13428.
This gives a better NOTE error message when a privacy error is encountered with
a static method. Previously no note was emitted (due to lack of support), but
now a note is emitted indicating that the struct/enum itself is private.
Closes#13641
This gives a better NOTE error message when a privacy error is encountered with
a static method. Previously no note was emitted (due to lack of support), but
now a note is emitted indicating that the struct/enum itself is private.
Closes#13641
When reporting "consider removing this semicolon" hint message, the
offending semicolon may come from macro call site instead of macro
itself. Using the more appropriate span makes the hint more helpful.
Closes#13428.
This commit changes the way move errors are reported when some value is
captured by a PatIdent. First, we collect all of the "cannot move out
of" errors before reporting them, and those errors with the same "move
source" are reported together. If the move is caused by a PatIdent (that
binds by value), we add a note indicating where it is and suggest the
user to put `ref` if they don't want the value to move. This makes the
"cannot move out of" error in match expression nicer (though the extra
note may not feel that helpful in other places :P). For example, with
the following code snippet,
```rust
enum Foo {
Foo1(~u32, ~u32),
Foo2(~u32),
Foo3,
}
fn main() {
let f = &Foo1(~1u32, ~2u32);
match *f {
Foo1(num1, num2) => (),
Foo2(num) => (),
Foo3 => ()
}
}
```
Errors before the change:
```rust
test.rs:10:9: 10:25 error: cannot move out of dereference of `&`-pointer
test.rs:10 Foo1(num1, num2) => (),
^~~~~~~~~~~~~~~~
test.rs:10:9: 10:25 error: cannot move out of dereference of `&`-pointer
test.rs:10 Foo1(num1, num2) => (),
^~~~~~~~~~~~~~~~
test.rs:11:9: 11:18 error: cannot move out of dereference of `&`-pointer
test.rs:11 Foo2(num) => (),
^~~~~~~~~
```
After:
```rust
test.rs:9:11: 9:13 error: cannot move out of dereference of `&`-pointer
test.rs:9 match *f {
^~
test.rs:10:14: 10:18 note: attempting to move value to here (to prevent the move, use `ref num1` or `ref mut num1` to capture value by reference)
test.rs:10 Foo1(num1, num2) => (),
^~~~
test.rs:10:20: 10:24 note: and here (use `ref num2` or `ref mut num2`)
test.rs:10 Foo1(num1, num2) => (),
^~~~
test.rs:11:14: 11:17 note: and here (use `ref num` or `ref mut num`)
test.rs:11 Foo2(num) => (),
^~~
```
Close#8064
This removes the `priv` keyword from the language and removes private enum
variants as a result. The remaining use cases of private enum variants were all
updated to be a struct with one private field that is a private enum.
RFC: 0006-remove-priv
Closes#13535
This includes a change to the way lifetime names are generated. Say we
figure that `[#0, 'a, 'b]` have to be the same lifetimes, then instead
of just generating a new lifetime `'c` like before to replace them, we
would reuse `'a`. This is done so that when the lifetime name comes
from an impl, we don't give something that's completely off, and we
don't have to do much work to figure out where the name came from. For
example, for the following code snippet:
```rust
struct Baz<'x> {
bar: &'x int
}
impl<'x> Baz<'x> {
fn baz1(&self) -> &int {
self.bar
}
}
```
`[#1, 'x]` (where `#1` is BrAnon(1) and refers to lifetime of `&int`)
have to be marked the same lifetime. With the old method, we would
generate a new lifetime `'a` and suggest `fn baz1(&self) -> &'a int`
or `fn baz1<'a>(&self) -> &'a int`, both of which are wrong.
A mismatched type with more type parameters than the expected one causes
`typeck` looking up out of the bound of type parameter vector, which
leads to ICE.
Closes#13466
A mismatched type with more type parameters than the expected one causes
`typeck` looking up out of the bound of type parameter vector, which
leads to ICE.
Closes#13466
Previously, a private use statement would shadow a public use statement, all of
a sudden publicly exporting the privately used item. The correct behavior here
is to only shadow the use for the module in question, but for now it just
reverts the entire name to private so the pub use doesn't have much effect.
The behavior isn't exactly what we want, but this no longer has backwards
compatibility hazards.
Previously resolve was checking the "import resolution" for whether an import
had succeeded or not, but this was the same structure filled in by a previous
import if a name is shadowed. Instead, this alters resolve to consult the local
resolve state (as opposed to the shared one) to test whether an import succeeded
or not.
Closes#13404
Resolve is currently erroneously allowing imports through private `use`
statements in some circumstances, even across module boundaries. For example,
this code compiles successfully today:
use std::c_str;
mod test {
use c_str::CString;
}
This should not be allowed because it was explicitly decided that private `use`
statements are purely bringing local names into scope, they are not
participating further in name resolution.
As a consequence of this patch, this code, while valid today, is now invalid:
mod test {
use std::c_str;
unsafe fn foo() {
::test::c_str::CString::new(0 as *u8, false);
}
}
While plausibly acceptable, I found it to be more consistent if private imports
were only considered candidates to resolve the first component in a path, and no
others.
Closes#12612
I think that the test case from this issue has become out of date with resolve
changes in the past 9 months, and it's not entirely clear to me what the
original bug was.
Regardless, it seems like tricky resolve behavior, so tests were added to make
sure things resolved correctly and warnings were correctly reported.
Closes#7663
This commit changes the way move errors are reported when some value is
captured by a PatIdent. First, we collect all of the "cannot move out
of" errors before reporting them, and those errors with the same "move
source" are reported together. If the move is caused by a PatIdent (that
binds by value), we add a note indicating where it is and suggest the
user to put `ref` if they don't want the value to move. This makes the
"cannot move out of" error in match expression nicer (though the extra
note may not feel that helpful in other places :P). For example, with
the following code snippet,
```rust
enum Foo {
Foo1(~u32, ~u32),
Foo2(~u32),
Foo3,
}
fn main() {
let f = &Foo1(~1u32, ~2u32);
match *f {
Foo1(num1, num2) => (),
Foo2(num) => (),
Foo3 => ()
}
}
```
Errors before the change:
```rust
test.rs:10:9: 10:25 error: cannot move out of dereference of `&`-pointer
test.rs:10 Foo1(num1, num2) => (),
^~~~~~~~~~~~~~~~
test.rs:10:9: 10:25 error: cannot move out of dereference of `&`-pointer
test.rs:10 Foo1(num1, num2) => (),
^~~~~~~~~~~~~~~~
test.rs:11:9: 11:18 error: cannot move out of dereference of `&`-pointer
test.rs:11 Foo2(num) => (),
^~~~~~~~~
```
After:
```rust
test.rs:9:11: 9:13 error: cannot move out of dereference of `&`-pointer
test.rs:9 match *f {
^~
test.rs:10:14: 10:18 note: attempting to move value to here (to prevent the move, you can use `ref num1` to capture value by reference)
test.rs:10 Foo1(num1, num2) => (),
^~~~
test.rs:10:20: 10:24 note: and here (use `ref num2`)
test.rs:10 Foo1(num1, num2) => (),
^~~~
test.rs:11:14: 11:17 note: and here (use `ref num`)
test.rs:11 Foo2(num) => (),
^~~
```
Close#8064
This fixes the categorization of the upvars of procs (represented internally
as once fns) to consider usage to require a loan. In doing so, upvars are no
longer allowed to be moved out of repeatedly in loops and such.
Closes#10398Closes#12041Closes#12127
In the error message for when a private field is used, include the name of the struct, or if it's a struct-like enum variant, the names of the variant and the enum.
This fixes#13341.
In summary these are some example transitions this change makes:
'a || => ||: 'a
proc:Send() => proc():Send
The intended syntax for closures is to put the lifetime bound not at the front
but rather in the list of bounds. Currently there is no official support in the
AST for bounds that are not 'static, so this case is currently specially handled
in the parser to desugar to what the AST is expecting. Additionally, this moves
the bounds on procedures to the correct position, which is after the argument
list.
The current grammar for closures and procedures is:
procedure := 'proc' [ '<' lifetime-list '>' ] '(' arg-list ')'
[ ':' bound-list ] [ '->' type ]
closure := [ 'unsafe' ] ['<' lifetime-list '>' ] '|' arg-list '|'
[ ':' bound-list ] [ '->' type ]
lifetime-list := lifetime | lifetime ',' lifetime-list
arg-list := ident ':' type | ident ':' type ',' arg-list
bound-list := bound | bound '+' bound-list
bound := path | lifetime
This does not currently handle the << ambiguity in `Option<<'a>||>`, I am
deferring that to a later patch. Additionally, this removes the support for the
obsolete syntaxes of ~fn and &fn.
Closes#10553Closes#10767Closes#11209Closes#11210Closes#11211
This can be a frustrating error message, ideally we should print the signature mismatch, but hinting that it's a trait incompatibility helps tracking root cause. Also beefed up the testcases for this.
Ideally we would print the signature mismatch in the error helper?
rustc: move the check_loop pass earlier.
This pass is purely AST based, and by running it earlier we emit more
useful error messages, e.g. type inference fails in the case of
`let r = break;` with few constraints on `r`, but it's more useful to be told that
the `break` is outside the loop (rather than a type error) when it is.
Closes#13292.
