These `where` clauses are accepted everywhere generics are currently
accepted and desugar during type collection to the type parameter bounds
we have today.
A new keyword, `where`, has been added. Therefore, this is a breaking
change. Change uses of `where` to other identifiers.
[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.
This patch primarily does two things: (1) it prevents lifetimes from
leaking out of unboxed closures; (2) it allows unboxed closure type
notation, call notation, and construction notation to construct closures
matching any of the three traits.
This breaks code that looked like:
let mut f;
{
let x = &5i;
f = |&mut:| *x + 10;
}
Change this code to avoid having a reference escape. For example:
{
let x = &5i;
let mut f; // <-- move here to avoid dangling reference
f = |&mut:| *x + 10;
}
I believe this is enough to consider unboxed closures essentially
implemented. Further issues (for example, higher-rank lifetimes) should
be filed as followups.
Closes#14449.
[breaking-change]
r? @pnkfelix
This patch primarily does two things: (1) it prevents lifetimes from
leaking out of unboxed closures; (2) it allows unboxed closure type
notation, call notation, and construction notation to construct closures
matching any of the three traits.
This breaks code that looked like:
let mut f;
{
let x = &5i;
f = |&mut:| *x + 10;
}
Change this code to avoid having a reference escape. For example:
{
let x = &5i;
let mut f; // <-- move here to avoid dangling reference
f = |&mut:| *x + 10;
}
I believe this is enough to consider unboxed closures essentially
implemented. Further issues (for example, higher-rank lifetimes) should
be filed as followups.
Closes#14449.
[breaking-change]
by-reference upvars.
This partially implements RFC 38. A snapshot will be needed to turn this
on, because stage0 cannot yet parse the keyword.
Part of #12831.
r? @alexcrichton
by-reference upvars.
This partially implements RFC 38. A snapshot will be needed to turn this
on, because stage0 cannot yet parse the keyword.
Part of #12381.
This adds support to `quote_expr!` and friends for round-trip hygienic
preservation of Ident.
Here are the pieces of the puzzle:
* adding a method for encoding Ident for re-reading into token tree.
* Support for reading such encoded Idents in the lexer. Note that one
must peek ahead for MOD_SEP after scan_embedded_hygienic_ident.
* To ensure that encoded Idents are only read when we are in the midst
of expanding a `quote_expr` or similar, added a
`read_embedded_ident` flag on `StringReader`.
* pprust support for encoding Ident's as (uint,uint) pairs (for hygiene).
For historical reasons, "Win32" has been used in Rust codebase to mean "Windows OS in general".
This is confusing, especially now, that Rust supports Win64 builds.
[breaking-change]
This is useful e.g. for tools need a node-id, such as the flowgraph
pretty printer, since it can avoids the need to first pretty-print the
whole expanded,identified input in order to find out what the node-id
actually is.
It currently only supports path suffixes thst are made up of module
names (e.g. you cannot use the type instantiation form `a::<int>::b`
or `option::Option::unwrap_or` as a path suffix for this tool, though
the tool will produce paths that have non-modulues in the portion of
the path that is not included in the suffix).
(addressed review feedback too)
This leaves the `Share` trait at `std::kinds` via a `#[deprecated]` `pub use`
statement, but the `NoShare` struct is no longer part of `std::kinds::marker`
due to #12660 (the build cannot bootstrap otherwise).
All code referencing the `Share` trait should now reference the `Sync` trait,
and all code referencing the `NoShare` type should now reference the `NoSync`
type. The functionality and meaning of this trait have not changed, only the
naming.
Closes#16281
[breaking-change]
This leaves the `Share` trait at `std::kinds` via a `#[deprecated]` `pub use`
statement, but the `NoShare` struct is no longer part of `std::kinds::marker`
due to #12660 (the build cannot bootstrap otherwise).
All code referencing the `Share` trait should now reference the `Sync` trait,
and all code referencing the `NoShare` type should now reference the `NoSync`
type. The functionality and meaning of this trait have not changed, only the
naming.
Closes#16281
[breaking-change]
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 ended up passing through the lexer but dying later on in parsing when it
wasn't handled. The strategy taken was to copy the `str_lit` funciton, but adapt
it for bytes.
Closes#16278
The `type_overflow` lint, doesn't catch the overflow for `i64` because
the overflow happens earlier in the parse phase when the `u64` as biggest
possible int gets casted to `i64` , without checking the for overflows.
We can't lint in the parse phase, so a refactoring of the `LitInt` type
was necessary.
The types `LitInt`, `LitUint` and `LitIntUnsuffixed` where merged to one
type `LitInt` which stores it's value as `u64`. An additional parameter was
added which indicate the signedness of the type and the sign of the value.
Note: This PR is motivated by an attempt to write an custom syntax extension that tried to use `syntax::fold`, and that could only do so by fixing bugs in it and copying out private functions.
---
Refactored `syntax::fold`
Prior to this, the code there had a few issues:
- Default implementations inconsistenly either had the prefix `noop_` or
not.
- Some default methods where implemented in terms of a public noop function
for user code to call, others where implemented directly on the trait
and did not allow users of the trait to reuse the code.
- Some of the default implementations where private, and thus not reusable
for other implementors.
- There where some bugs where default implemntations called other default
implementations directly, rather than to the underlying Folder, with the
result of some ast nodes never being visted even if the user implemented that
method. (For example, the current Folder never folded struct fields)
This commit solves this situation somewhat radically by making __all__
`fold_...` functions in the module into Folder methods, and implementing
them all in terms of public `noop_...` functions for other implementors to
call out to.
Some public functions had to be renamed to fit the new system, so this is a
breaking change.
---
Also added a few trait implementations to `ast` types
Not included are two required patches:
* LLVM: segmented stack support for DragonFly [1]
* jemalloc: simple configure patches
[1]: http://reviews.llvm.org/D4705
This adds support for `quote_arm!(cx, $pat => $expr)`, and `macro_rules!(($a:arm) => (...))`. It also fixes a bug in pretty printing, where this would generate invalid code:
```
match { 5i } {
1 => 2,
_ => 3,
}
```
It would generate this code:
```
match { 5i } {
1 => 2
_ => 3
}
```
Finally, it adds a couple helper methods to `ExtCtxt`.
Not included are two required patches:
* LLVM: segmented stack support for DragonFly [1]
* jemalloc: simple configure patches
[1]: http://reviews.llvm.org/D4705
Prior to this, the code there had a few issues:
- Default implementations inconsistently either had the prefix `noop_` or
not.
- Some default methods where implemented in terms of a public noop function
for user code to call, others where implemented directly on the trait
and did not allow users of the trait to reuse the code.
- Some of the default implementations where private, and thus not reusable
for other implementors.
- There where some bugs where default implementations called other default
implementations directly, rather than to the underlying Folder, with the
result of some AST nodes never being visited even if the user implemented that
method. (For example, the current Folder never folded struct fields)
This commit solves this situation somewhat radically by making _all_
`fold_...` functions in the module into Folder methods, and implementing
them all in terms of public `noop_...` functions for other implementors to
call out to.
Some public functions had to be renamed to fit the new system, so this is a
breaking change.
[breaking-change]
the CFG for match statements.
There were two bugs in issue #14684. One was simply that the borrow
check didn't know about the correct CFG for match statements: the
pattern must be a predecessor of the guard. This disallows the bad
behavior if there are bindings in the pattern. But it isn't enough to
prevent the memory safety problem, because of wildcards; thus, this
patch introduces a more restrictive rule, which disallows assignments
and mutable borrows inside guards outright.
I discussed this with Niko and we decided this was the best plan of
action.
This breaks code that performs mutable borrows in pattern guards. Most
commonly, the code looks like this:
impl Foo {
fn f(&mut self, ...) {}
fn g(&mut self, ...) {
match bar {
Baz if self.f(...) => { ... }
_ => { ... }
}
}
}
Change this code to not use a guard. For example:
impl Foo {
fn f(&mut self, ...) {}
fn g(&mut self, ...) {
match bar {
Baz => {
if self.f(...) {
...
} else {
...
}
}
_ => { ... }
}
}
}
Sometimes this can result in code duplication, but often it illustrates
a hidden memory safety problem.
Closes#14684.
[breaking-change]
This makes edge cases in which the `Iterator` trait was not in scope
and/or `Option` or its variants were not in scope work properly.
This breaks code that looks like:
struct MyStruct { ... }
impl MyStruct {
fn next(&mut self) -> Option<int> { ... }
}
for x in MyStruct { ... } { ... }
Change ad-hoc `next` methods like the above to implementations of the
`Iterator` trait. For example:
impl Iterator<int> for MyStruct {
fn next(&mut self) -> Option<int> { ... }
}
Closes#15392.
[breaking-change]
This is done entirely in the libraries for functions up to 16 arguments.
A macro is used so that more arguments can be easily added if we need.
Note that I had to adjust the overloaded call algorithm to not try
calling the overloaded call operator if the callee is a built-in
function type, to prevent loops.
Closes#15448.
This eliminates the last vestige of the `~` syntax.
Instead of `~self`, write `self: Box<TypeOfSelf>`; instead of `mut
~self`, write `mut self: Box<TypeOfSelf>`, replacing `TypeOfSelf` with
the self-type parameter as specified in the implementation.
Closes#13885.
[breaking-change]
Emit a single rt::Piece per consecutive string literals. String literals
are split on {{ or }} escapes.
Saves a small amount of static storage and emitted code size.
In f1ad425199, I changed the handling
of macros, to prevent macro invocations from occurring in fully expanded
source. Instead, I added a side table. It contained only the
spans of the macros, because this was the only information required
in order to make macro export work.
However, librustdoc was also affected by this change, since it
extracts macro information in a similar way. As a result of the earlier
change, exported macros were no longer documented.
In order to repair this, I've adjusted the side table to contain whole
items, rather than just the spans.
except where trait objects are involved.
Part of issue #15349, though I'm leaving it open for trait objects.
Cross borrowing for trait objects remains because it is needed until we
have DST.
This will break code like:
fn foo(x: &int) { ... }
let a = box 3i;
foo(a);
Change this code to:
fn foo(x: &int) { ... }
let a = box 3i;
foo(&*a);
[breaking-change]
This makes two changes to region inference: (1) it allows region
inference to relate early-bound regions; and (2) it allows regions to be
related before variance runs. The former is needed because there is no
relation between the two regions before region substitution happens,
while the latter is needed because type collection has to run before
variance. We assume that, before variance is inferred, that lifetimes
are invariant. This is a conservative overapproximation.
This relates to #13885. This does not remove `~self` from the language
yet, however.
[breaking-change]
This patch applies the excellent suggestion of @pnkfelix to group the helper methods for method field access into a Trait, making the code much more readable, and much more similar to the way it was before.
Per @pnkfelix 's suggestion, using a trait to make these
field accesses more readable (and vastly more similar
to the original code.
oops fix new ast_map fix
please note the snapshot-waiting unpleasantness. I'm
unable to use the traditional #[cfg(stage0)] mechanism
to swap the new style in for later compiler stages,
because macros invocations in method positions cause
the parser to choke before cfg can strip it out.
Parenthetical note: this problem wouldn't arise with
an interleaved parsing/expansion....
Use one or more of the following `-Z` flag options to tell the
graphviz renderer to include the corresponding dataflow sets (after
the iterative constraint propagation reaches a fixed-point solution):
* `-Z flowgraph-print-loans` : loans computed via middle::borrowck
* `-Z flowgraph-print-moves` : moves computed via middle::borrowck::move_data
* `-Z flowgraph-print-assigns` : assignments, via middle::borrowck::move_data
* `-Z flowgraph-print-all` : all of the available sets are included.
Fix#15016.
----
This also adds a module, `syntax::ast_map::blocks`, that captures a
common abstraction shared amongst code blocks and procedure-like
things. As part of this, moved `ast_map.rs` to subdir
`ast_map/mod.rs`, to follow our directory layout conventions.
(incorporated review feedback from huon, acrichto.)
This patch adds support for macros in method position. It follows roughly the template for Item macros, where an outer `Method` wrapper contains a `Method_` enum which can either be a macro invocation or a standard macro definition.
One note; adding support for macros that expand into multiple methods is not included here, but should be a simple parser change, since this patch updates the type of fold_macro to return a smallvector of methods.
For reviewers, please pay special attention to the parser changes; these are the ones I'm most concerned about.
Because of the small change to the interface of fold_method, this is a ...
[breaking change]