followed by a semicolon.
This allows code like `vec![1i, 2, 3].len();` to work.
This breaks code that uses macros as statements without putting
semicolons after them, such as:
fn main() {
...
assert!(a == b)
assert!(c == d)
println(...);
}
It also breaks code that uses macros as items without semicolons:
local_data_key!(foo)
fn main() {
println("hello world")
}
Add semicolons to fix this code. Those two examples can be fixed as
follows:
fn main() {
...
assert!(a == b);
assert!(c == d);
println(...);
}
local_data_key!(foo);
fn main() {
println("hello world")
}
RFC #378.
Closes#18635.
[breaking-change]
This change makes the compiler no longer infer whether types (structures
and enumerations) implement the `Copy` trait (and thus are implicitly
copyable). Rather, you must implement `Copy` yourself via `impl Copy for
MyType {}`.
A new warning has been added, `missing_copy_implementations`, to warn
you if a non-generic public type has been added that could have
implemented `Copy` but didn't.
For convenience, you may *temporarily* opt out of this behavior by using
`#![feature(opt_out_copy)]`. Note though that this feature gate will never be
accepted and will be removed by the time that 1.0 is released, so you should
transition your code away from using it.
This breaks code like:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
Change this code to:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
impl Copy for Point2D {}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
This is the backwards-incompatible part of #13231.
Part of RFC #3.
[breaking-change]
This change applies the conventions to unwrap listed in [RFC 430][rfc] to rename
non-failing `unwrap` methods to `into_inner`. This is a breaking change, but all
`unwrap` methods are retained as `#[deprecated]` for the near future. To update
code rename `unwrap` method calls to `into_inner`.
[rfc]: https://github.com/rust-lang/rfcs/pull/430
[breaking-change]
Closes#13159
cc #19091
This breaks code that referred to variant names in the same namespace as
their enum. Reexport the variants in the old location or alter code to
refer to the new locations:
```
pub enum Foo {
A,
B
}
fn main() {
let a = A;
}
```
=>
```
pub use self::Foo::{A, B};
pub enum Foo {
A,
B
}
fn main() {
let a = A;
}
```
or
```
pub enum Foo {
A,
B
}
fn main() {
let a = Foo::A;
}
```
[breaking-change]
- The signature of the `*_equiv` methods of `HashMap` and similar structures
have changed, and now require one less level of indirection. Change your code
from:
```
hashmap.find_equiv(&"Hello");
hashmap.find_equiv(&&[0u8, 1, 2]);
```
to:
```
hashmap.find_equiv("Hello");
hashmap.find_equiv(&[0u8, 1, 2]);
```
- The generic parameter `T` of the `Hasher::hash<T>` method have become
`Sized?`. Downstream code must add `Sized?` to that method in their
implementations. For example:
```
impl Hasher<FnvState> for FnvHasher {
fn hash<T: Hash<FnvState>>(&self, t: &T) -> u64 { /* .. */ }
}
```
must be changed to:
```
impl Hasher<FnvState> for FnvHasher {
fn hash<Sized? T: Hash<FnvState>>(&self, t: &T) -> u64 { /* .. */ }
// ^^^^^^
}
```
[breaking-change]
https://github.com/rust-lang/rfcs/pull/221
The current terminology of "task failure" often causes problems when
writing or speaking about code. You often want to talk about the
possibility of an operation that returns a Result "failing", but cannot
because of the ambiguity with task failure. Instead, you have to speak
of "the failing case" or "when the operation does not succeed" or other
circumlocutions.
Likewise, we use a "Failure" header in rustdoc to describe when
operations may fail the task, but it would often be helpful to separate
out a section describing the "Err-producing" case.
We have been steadily moving away from task failure and toward Result as
an error-handling mechanism, so we should optimize our terminology
accordingly: Result-producing functions should be easy to describe.
To update your code, rename any call to `fail!` to `panic!` instead.
Assuming you have not created your own macro named `panic!`, this
will work on UNIX based systems:
grep -lZR 'fail!' . | xargs -0 -l sed -i -e 's/fail!/panic!/g'
You can of course also do this by hand.
[breaking-change]
Spring cleaning is here! In the Fall! This commit removes quite a large amount
of deprecated functionality from the standard libraries. I tried to ensure that
only old deprecated functionality was removed.
This is removing lots and lots of deprecated features, so this is a breaking
change. Please consult the deprecation messages of the deleted code to see how
to migrate code forward if it still needs migration.
[breaking-change]
Since a large number of lints are being renamed for RFC 344, this commit
adds some basic deprecation/renaming functionality to the pluggable lint
system. It allows a simple mapping of old to new names, and can warn
when old names are being used.
This change needs to be rolled out in stages. In this commit, the
deprecation warning is commented out, but the old name is forwarded to
the new one.
Once the commit lands and we have generated a new snapshot of the
compiler, we can add the deprecation warning and rename all uses of the
lints in the rust codebase.
RFC 344 proposes a set of naming conventions for lints. This commit
renames existing lints to follow the conventions.
Use the following sed script to bring your code up to date:
```
s/unnecessary_typecast/unused_typecasts/g
s/unsigned_negate/unsigned_negation/g
s/type_limits/unused_comparisons/g
s/type_overflow/overflowing_literals/g
s/ctypes/improper_ctypes/g
s/owned_heap_memory/box_pointers/g
s/unused_attribute/unused_attributes/g
s/path_statement/path_statements/g
s/unused_must_use/unused_must_use/g
s/unused_result/unused_results/g
s/non_uppercase_statics/non_upper_case_globals/g
s/unnecessary_parens/unused_parens/g
s/unnecessary_import_braces/unused_import_braces/g
s/unused_unsafe/unused_unsafe/g
s/unsafe_block/unsafe_blocks/g
s/unused_mut/unused_mut/g
s/unnecessary_allocation/unused_allocation/g
s/missing_doc/missing_docs/g
s/unused_imports/unused_imports/g
s/unused_extern_crate/unused_extern_crates/g
s/unnecessary_qualification/unused_qualifications/g
s/unrecognized_lint/unknown_lints/g
s/unused_variable/unused_variables/g
s/dead_assignment/unused_assignments/g
s/unknown_crate_type/unknown_crate_types/g
s/variant_size_difference/variant_size_differences/g
s/transmute_fat_ptr/fat_ptr_transmutes/g
```
Closes#16545Closes#17932
Due to deprecation, this is a:
[breaking-change]
The implementation essentially desugars during type collection and AST
type conversion time into the parameter scheme we have now. Only fully
qualified names--e.g. `<T as Foo>::Bar`--are supported.
This PR creates a new lint : ``unused_extern_crate``, which do pretty much the same thing as ``unused_import``, but for ``extern crate`` statements. It is related to feature request #10385.
I adapted the code tracking used imports so that it tracks extern crates usage as well. This was mainly trial and error and while I believe all cases are covered, there might be some code I added that is useless (long compile times didn't give me the opportunity to check this in detail).
Also, I removed some unused ``extern crate`` statements from the libs, that where spotted by this new lint.
This adds support for lint groups to the compiler. Lint groups are a way of
grouping a number of lints together under one name. For example, this also
defines a default lint for naming conventions, named `bad_style`. Writing
`#[allow(bad_style)]` is equivalent to writing
`#[allow(non_camel_case_types, non_snake_case, non_uppercase_statics)]`. These
lint groups can also be defined as a compiler plugin using the new
`Registry::register_lint_group` method.
This also adds two built-in lint groups, `bad_style` and `unused`. The contents
of these groups can be seen by running `rustc -W help`.
This unifies the `non_snake_case_functions` and `uppercase_variables` lints
into one lint, `non_snake_case`. It also now checks for non-snake-case modules.
This also extends the non-camel-case types lint to check type parameters, and
merges the `non_uppercase_pattern_statics` lint into the
`non_uppercase_statics` lint.
Because the `uppercase_variables` lint is now part of the `non_snake_case`
lint, all non-snake-case variables that start with lowercase characters (such
as `fooBar`) will now trigger the `non_snake_case` lint.
New code should be updated to use the new `non_snake_case` lint instead of the
previous `non_snake_case_functions` and `uppercase_variables` lints. All use of
the `non_uppercase_pattern_statics` should be replaced with the
`non_uppercase_statics` lint. Any code that previously contained non-snake-case
module or variable names should be updated to use snake case names or disable
the `non_snake_case` lint. Any code with non-camel-case type parameters should
be changed to use camel case or disable the `non_camel_case_types` lint.
[breaking-change]
methods.
This paves the way to associated items by introducing an extra level of
abstraction ("impl-or-trait item") between traits/implementations and
methods. This new abstraction is encoded in the metadata and used
throughout the compiler where appropriate.
There are no functional changes; this is purely a refactoring.
meaning `'b outlives 'a`. Syntax currently does nothing but is needed for full
fix to #5763. To use this syntax, the issue_5763_bootstrap feature guard is
required.
This is an alternative to upgrading the way rvalues are handled in the
borrow check. Making rvalues handled more like lvalues in the borrow
check caused numerous problems related to double mutable borrows and
rvalue scopes. Rather than come up with more borrow check rules to try
to solve these problems, I decided to just forbid pattern bindings after
`@`. This affected fewer than 10 lines of code in the compiler and
libraries.
This breaks code like:
match x {
y @ z => { ... }
}
match a {
b @ Some(c) => { ... }
}
Change this code to use nested `match` or `let` expressions. For
example:
match x {
y => {
let z = y;
...
}
}
match a {
Some(c) => {
let b = Some(c);
...
}
}
Closes#14587.
[breaking-change]
