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]
This change propagates to many locations, but because of the
Macro Exterminator (or, more properly, the invariant that it
protects), macro invocations can't occur downstream of expansion.
This means that in librustc and librustdoc, extracting the
desired field can simply assume that it can't be a macro
invocation. Functions in ast_util abstract over this check.
* Don't warn about `#[crate_name]` if `--crate-name` is specified
* Don't warn about non camel case identifiers on `#[repr(C)]` structs
* Switch `mode` to `mode_t` in libc.
They used to be one token too long, so you'd see things like
```
rust/rust/test.rs:1:1: 2:2 warning: unused attribute,
rust/rust/test.rs:1 #![foo]
rust/rust/test.rs:2 #![bar]
```
instead of
```
test.rs:1:1: 1:8 warning: unused attribute, #[warn(unused_attribute)] on
by default
test.rs:1 #![foo]
^~~~~~~
```
Our AST definition can include macro invocations, which can expand into all kinds of things. Macro invocations are expanded away during expansion time, and the rest of the compiler doesn't have to deal with them. However, we have no way of enforcing this.
This patch adds two protective mechanisms.
First, it adds a (quick) explicit check that ensures there are no macro invocations remaining in the AST after expansion. Second, it updates the visit and fold mechanisms so that by default, they will not traverse macro invocations. It's easy enough to add this, if desired (it's documented in the source, and examples appear, e.g. in the IdentFinder.
Along the way, I also consulted with @sfackler to refactor the macro export mechanism so that it stores macro text spans in a side table, rather than leaving them in the AST.
They used to be one token too long, so you'd see things like
```
rust/rust/test.rs:1:1: 2:2 warning: unused attribute,
rust/rust/test.rs:1 #![foo]
rust/rust/test.rs:2 #![bar]
```
instead of
```
test.rs:1:1: 1:8 warning: unused attribute, #[warn(unused_attribute)] on
by default
test.rs:1 #![foo]
^~~~~~~
```
the Macro Exterminator ensures that there are no macro invocations in
an AST. This should help make later passes confident that there aren't
hidden items, methods, expressions, etc.
macros can expand into arbitrary items, exprs, etc. This
means that using a default walker or folder on an AST before
macro expansion is complete will miss things (the things that
the macros expand into). As a partial fence against this, this
commit moves the default traversal of macros into a separate
procedure, and makes the default trait implementation signal
an error. This means that Folders and Visitors can traverse
macros if they want to, but they need to explicitly add an
impl that calls the walk_mac or fold_mac procedure
This should prevent problems down the road.
Per discussion with @sfackler, refactored the expander to
change the way that exported macros are collected. Specifically,
a crate now contains a side table of spans that exported macros
go into.
This has two benefits. First, the encoder doesn't need to scan through
the expanded crate in order to discover exported macros. Second, the
expander can drop all expanded macros from the crate, with the pleasant
result that a fully expanded crate contains no macro invocations (which
include macro definitions).
Remove the `NonMatchesExplode` variant now that no deriving impl uses it.
Removed `EnumNonMatching` entirely.
Remove now irrelevant `on_matching` field and `HandleNonMatchingEnums` type.
Removed unused `EnumNonMatchFunc` type def.
Drive-by: revise `EnumNonMatchCollapsedFunc` doc.
Made all calls to `expand_enum_method_body` go directly to
`build_enum_match_tuple`.
Alpha-rename `enum_nonmatch_g` back to `enum_nonmatch_f` to reduce overall diff noise.
Inline sole call of `some_ordering_const`.
Inline sole call of `ordering_const`.
Removed a bunch of code that became dead after the above changes.
In the above formulas, `n` is the number of variants, and `k` is the
number of self-args fed into deriving. In the particular case of
interest (namely `PartialOrd` and `Ord`), `k` is always 2, so we are
basically comparing `O(n)` versus `O(n^2)`.
Also, the stage is set for having *all* enum deriving codes go through
`build_enum_match_tuple` and getting rid of `build_enum_match`.
Also, seriously attempted to clean up the code itself. Added a bunch
of comments attempting to document what I learned as I worked through
the original code and adapted it to this new strategy.
In particular, I want authors of deriving modes to understand what
they are opting into (namely quadratic code size or worse) when they
select NonMatchesExplode.
Now, the lexer will categorize every byte in its input according to the
grammar. The parser skips over these while parsing, thus avoiding their
presence in the input to syntax extensions.
This removes a bunch of token types. Tokens now store the original, unaltered
numeric literal (that is still checked for correctness), which is parsed into
an actual number later, as needed, when creating the AST.
This can change how syntax extensions work, but otherwise poses no visible
changes.
[breaking-change]
This shuffles things around a bit so that LIT_CHAR and co store an Ident
which is the original, unaltered literal in the source. When creating the AST,
unescape and postprocess them.
This changes how syntax extensions can work, slightly, but otherwise poses no
visible changes. To get a useful value out of one of these tokens, call
`parse::{char_lit, byte_lit, bin_lit, str_lit}`
[breaking-change]
Rather than just dumping the id in the interner, which is useless, actually
print the interned string. Adjust the lexer logging to use Show instead of
Poly.
formerly, the self identifier was being discarded during parsing, which
stymies hygiene. The best fix here seems to be to attach a self identifier
to ExplicitSelf_, a change that rippled through the rest of the compiler,
but without any obvious damage.
The let-syntax expander is different in that it doesn't apply
a mark to its token trees before expansion. This is used
for macro_rules, and it's because macro_rules is essentially
MTWT's let-syntax. You don't want to mark before expand sees
let-syntax, because there's no "after" syntax to mark again.
In some sense, the cleaner approach might be to introduce a new
AST node that macro_rules expands into; this would make it clearer
that the expansion of a macro is distinct from the addition of a
new macro binding.
This should work for now, though...
This updates https://github.com/rust-lang/rust/pull/15075.
Rename `ToStr::to_str` to `ToString::to_string`. The naive renaming ends up with two `to_string` functions defined on strings in the prelude (the other defined via `collections::str::StrAllocating`). To remedy this I removed `StrAllocating::to_string`, making all conversions from `&str` to `String` go through `Show`. This has a measurable impact on the speed of this conversion, but the sense I get from others is that it's best to go ahead and unify `to_string` and address performance for all `to_string` conversions in `core::fmt`. `String::from_str(...)` still works as a manual fast-path.
Note that the patch was done with a script, and ended up renaming a number of other `*_to_str` functions, particularly inside of rustc. All the ones I saw looked correct, and I didn't notice any additional API breakage.
Closes#15046.
closes#13367
[breaking-change] Use `Sized?` to indicate a dynamically sized type parameter or trait (used to be `type`). E.g.,
```
trait Tr for Sized? {}
fn foo<Sized? X: Share>(x: X) {}
```
This commit removes all support in the compiler for the #[crate_id] attribute
and all of its derivative infrastructure. A list of the functionality removed is:
* The #[crate_id] attribute no longer exists
* There is no longer the concept of a version of a crate
* Version numbers are no longer appended to symbol names
* The --crate-id command line option has been removed
To migrate forward, rename #[crate_id] to #[crate_name] and only the name of the
crate itself should be mentioned. The version/path of the old crate id should be
removed.
For a transitionary state, the #[crate_id] attribute is still accepted if
the #[crate_name] is not present, but it is warned about if it is the only
identifier present.
RFC: 0035-remove-crate-id
[breaking-change]
This pull request adds hygiene for 3 kinds of argument bindings:
- arguments to item fns,
- arguments to `ExprFnBlock`s, and
- arguments to `ExprProc`s
It also adds a bunch of unit tests, fixes a few macro uses to be non-capturing, and has a few cleanup items.
local `make check` succeeds.
This was parsed by the parser but completely ignored; not even stored in
the AST!
This breaks code that looks like:
static X: &'static [u8] = &'static [1, 2, 3];
Change this code to the shorter:
static X: &'static [u8] = &[1, 2, 3];
Closes#15312.
[breaking-change]
Rationale: for what appear to be historical reasons only, the PatIdent contains
a Path rather than an Ident. This means that there are many places in the code
where an ident is artificially promoted to a path, and---much more problematically---
a bunch of elements from a path are simply thrown away, which seems like an invitation
to some really nasty bugs.
This commit replaces the Path in a PatIdent with a SpannedIdent, which just contains an ident
and a span.
Being able to index into the bytes of a string encourages
poor UTF-8 hygiene. To get a view of `&[u8]` from either
a `String` or `&str` slice, use the `as_bytes()` method.
Closes#12710.
[breaking-change]
I ended up altering the semantics of Json's PartialOrd implementation.
It used to be the case that Null < Null, but I can't think of any reason
for an ordering other than the default one so I just switched it over to
using the derived implementation.
This also fixes broken `PartialOrd` implementations for `Vec` and
`TreeMap`.
RFC: 0028-partial-cmp
floating point numbers for real.
This will break code that looks like:
let mut x = 0;
while ... {
x += 1;
}
println!("{}", x);
Change that code to:
let mut x = 0i;
while ... {
x += 1;
}
println!("{}", x);
Closes#15201.
[breaking-change]
This change registers new snapshots, allowing `*T` to be removed from the language. This is a large breaking change, and it is recommended that if compiler errors are seen that any FFI calls are audited to determine whether they should be actually taking `*mut T`.
I believe that #5781 got fixed by the DST work. It duplicated the
variance inference work in #12828. Therefore, all that is left in #5781
is adding a test.
Closes#5781.
r? @huonw
This can break code that looked like:
impl Foo for Box<Any> {
fn f(&self) { ... }
}
let x: Box<Any + Send> = ...;
x.f();
Change such code to:
impl Foo for Box<Any> {
fn f(&self) { ... }
}
let x: Box<Any> = ...;
x.f();
That is, upcast before calling methods.
This is a conservative solution to #5781. A more proper treatment (see
the xfail'd `trait-contravariant-self.rs`) would take variance into
account. This change fixes the soundness hole.
Some library changes had to be made to make this work. In particular,
`Box<Any>` is no longer showable, and only `Box<Any+Send>` is showable.
Eventually, this restriction can be lifted; for now, it does not prove
too onerous, because `Any` is only used for propagating the result of
task failure.
This patch also adds a test for the variance inference work in #12828,
which accidentally landed as part of DST.
Closes#5781.
[breaking-change]
This PR includes two big things and a bunch of little ones.
1) It enables hygiene for variables bound by 'match' expressions.
2) It fixes a bug discovered indirectly (#15221), wherein fold traversal failed to visit nonterminal nodes.
3) It fixes a small bug in the macro tutorial.
It also adds tests for the first two, and makes a bunch of small comment improvements and cleanup.