This proposal renames the syntax used to mark an overriding definition
of a virtual method from `impl fn` to `override fn` to avoid ambiguity:
besides indicating an overriding virtual function, it can be parsed as
an "impl" declaration when the construct following "impl" begins with a
lambda introduced by "fn".
Closes#5711
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Co-authored-by: Richard Smith <richard@metafoo.co.uk>
Decouples associated constants from being special cased in let handlers.
Enforces associated constant grammar restrictions in parsing instead of
checking.
Closes#5411
Following the direction of #5913, add support for parsing an `unsafe as`
operator. For now, we allow one additional conversion using `unsafe as`
beyond the conversions supported by `as`: we permit pointer conversions
that remove qualifiers, such as `const T*` -> `T*`.
We add a virtual node (`CompileTimeBindingPatternStart`) as the first
child of `CompileTimeBindingPattern` which holds the identifier
underneath it, so that it is checked just before the type expression of
the `CompileTimeBindingPattern`. When we reach this virtual node during
check, we add `.Self` as a name in the current scope, and when we reach
`CompileTimeBindingPattern` we remove it from scope, which ensures it's
present during only the checking of the type expression for the compile
time pattern.
At the moment the `.Self` has a different type (it's a `TypeType`) than
other `.Self` in the facet type (which are a single `FacetType`), but
the intention is to immediately substitute it out of the facet type
entirely, replacing it with a reference to the compile time binding (a
`BindSymbolicName`) itself. A TODO has been added for this.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
toolchain/check/testdata/builtins/char/basics.carbon and
toolchain/lower/testdata/builtins/char.carbon are probably the most
interesting tests here. The parse tests is required because this adds a
new node kind, and we need coverage of it; but the attached info is
minor. There's a fair amount of test churn here because I'm adding the
Core.Char and Core.CharLiteral types as new singletons.
My intent here is that `CharId` is always a unicode code point, even
when the type is a `Char` and thus must be a single UTF-8 code unit
(single byte). This mainly means the stored value of a `CharValue` can
be printed internally without knowing the type.
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Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
This adds support for importing C++ code directly from source rather
than via a `#include`.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
In line with the proposal in #4682, this changes the array syntax to be
array(T, N). `array` is a builtin keyword which must be followed by
parens containing two expressions and a separating comma.
The array type expression is still fully builtin, it does not forward to
a Core.Array library type yet. It merely adds the `ArrayType`
instruction, as was done with the previous syntax.
Followup work will change the instruction to reference to Core.Array,
once the library type exists and can be used directly.
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Co-authored-by: zygoloid <richard@metafoo.co.uk>
Parameter lists need substantially different treatment than tuple
patterns in other contexts, so this change splits them into separate
parse node kinds.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
When I open a .def file, there are often 4 errors:
- The #error
- The #define is not defined
- Missing `;`
- Identifier naming
This PR is meant to disable all of these, since they can be distracting
from fixable diagnostics.
Change parse tree from `template (T:! type)` to `(template T):! type`,
so that we have information about whether a binding is a template
binding available when forming the representation of the binding
pattern. This incidentally fixes a bug that we would accept `template
addr A:! B` instead of the intended `addr template A:! B`.
Track whether a symbolic binding is a template binding on the
`EntityName` object. I'm borrowing a bit from the `CompileTimeBindIndex`
for this in order to avoid making `EntityName`s larger. Longer-term, we
should think about using a different representation for symbolic
bindings, to avoid including these fields in all `EntityName`s, but
that's out of scope for this change.
So far, template bindings are treated as having the same phase as
checked bindings, but that will change in a future PR.
To do this, we restructure the parse tree to make `forall` a leaf node
that comes before the parameter list.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Change representation of package names from `IdentifierId` to
`PackageNameId`, and add a special value `PackageNameId::Core` for the
Core package. Add a `Core` expression to name the Core package, and
support for parsing the `Core` keyword in `package` and `import`
declarations.
For now, I've made no changes to instruction fingerprinting or name
mangling. This means that fingerprints and mangled names will collide
between names in the `Core` package and names in a `r#Core` package. See
#4908.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
This change splits `NodeKind::IdentifierName` into separate node kinds
depending on whether the identifier is followed by parameters, and
similarly splits `NameQualifier` based on whether the qualifier has
parameters. This enables us to only push a pattern block when it's
actually needed, rather than "defensively" pushing one when it might be
needed.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Split StructComma into StructLiteralComma and StructTypeLiteralComma in
order to easily differentiate handling (remains the same in this PR).
Add "Literal" to StructField and StructTypeField because it feels
inconsistent versus the other non-shared things. StructFieldDesignator
remains shared between value literals and type literals.
Note I probably would've made StructFieldDesignator non-shared too, but
that'd require either a lookahead of 2 (to see the separator`) or a
writeback after parsing the separator, neither of which felt especially
crucial for this, when what I'm really trying to do is split type
literal handling a little further.
Includes support for the `impls`, `=`, and `==` requirement operators to
the right of a `where`, but `and` to allow multiple requirements is
still a TODO.
---------
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
These appear in `where` clauses, as in:
```
U:! InterfaceB where .C = Vector(.D)
V:! type where Vector(.Self) impls Sortable
```
`.Self` can additionally appear in type expressions in a binding pattern
such as `T:! InterfaceA(.Self)`.
---------
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Instead of tracking the token associated with a parse node in the `.def`
file macro, track it on the typed node instead. List the token as a
field inside the node structure to show the order of the token relative
to the other components of the grammar production, and to allow the
token index to be accessed when the node is extracted.
Remove the corresponding information from the `.def` file, leaving
behind just a list of parse node kinds in the majority of cases.
This also removes the checking of the token kind associated with a parse
node in the case where the parse node has errors. Previously we had a
flag on the node kind to indicate whether we should check this, but per
[discord
discussion](https://discord.com/channels/655572317891461132/655578254970716160/1246214418979881052),
we have decided to remove this.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Instead of tracking the bracketing and child count information in the
kind macro in `node_kind.def`, provide it to `NodeKind::Define` in
`typed_nodes.h`. If a node is both bracketed and has a fixed child
count, track both facts and check them both in tree verification, since
it's easy to do so now.
The overall goal here is to reduce `node_kind.def` down to a simple list
of names. I have a slightly different approach in mind for the token
kinds.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Co-authored-by: Carbon Infra Bot <carbon-external-infra@google.com>
Parse the name of a declaration as a sequence of `NameQualifier`s --
which have a name, possibly parameters, and a trailing period --
followed by a name and possibly parameters. This prepares us for parsing
declarations of members of generic classes and similar cases, but
actually supporting such member redeclarations is left to a future
change.
We previously required functions to have parameters, but no longer do,
following the direction of #3848. Cases like namespaces that can't
actually have parameters are now diagnosed in check instead of in parse.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Change syntax for package declaration to put the `impl` keyword at the
start and remove the `api` keyword.
To support this, rearrange processing of package, library, and import
declarations to use the general modifier handling support in declaration
parsing rather than special-case logic.
There is an ambiguity in `impl package.Foo as Bar`, which we resolve by
treating `package` as an introducer after a modifier only if it's not
followed by `.`.
This provides `export import` logic in lex, parse, and check; `export
name` logic is only in lex and parse, not check.
I think with `export name` I'm going to need to modify import_ref and
some consolidation logic, whereas `export import` seems feasible to keep
as primarily import logic. Given the implementations were looking like
they'd diverge more substantially, I thought it'd be helpful to cut the
PR here.
This is achieving a similar goal as #3849, using placeholders instead of
an ambiguous start node to clarify structure and incrementally simplify
checking. The benefit isn't quite as big here because both paths are
structs, and so checking is more consistent than paren exprs versus
tuples. But I think this removes the only other multi-purpose parse
node.
This uses StructLiteral/StructTypeLiteral naming, reflecting equivalent
SemIR naming. Note, I would lean towards renaming StructLiteral to
StructValueLiteral, but I think consistency in naming takes precedence.
Any renames of StructLiteral might be better in a separate PR.
StructFieldType/StructFieldValue -> StructTypeField/StructField is
trying to making the reading more consistent with
StructTypeLiteral/StructLiteral. SemIR has StructTypeField but not a
value equivalent.
I've been thinking about this since we decided to add placeholders in
the parse tree. This allows a clearer division of work in check
handling, where we were doing work for ExprOpenParen that's only
necessary for tuples (splitting/renaming handle_paren.cpp accordingly).
For now, a builtin function is defined by specifying a string literal
initializer in a function declaration:
```carbon
fn MyBuiltin(a: i32) -> i32 = "builtin.name";
```
End-to-end support is included for a sample `"int.add"` builtin
performing integer addition, covering constant evaluation and code
generation.
The implementation here needs substantial refactoring before we'll be
ready to start adding more builtins. That refactoring work will be
coming next. This change is aiming to checkpoint some incremental
progress.
This doesn't add full support. I'm separating it out to make the effects
of the modifier changes clearer for review. I'm restructuring a little
with the expectation that we'll have some more categories of modifier
keywords in the future (similar to `extern`, these may not be in a "set"
such as access), and thus easily scaling up to a few more would be
useful.
This undoes parts of #3515 in order to allow PushGlobalInit to be called
when the initializer is called, instead of at the end of the binding
pattern. The current approach is fragile because supported patterns will
become more complex. We also will likely want similar support in `let`,
which puts the initializer first, so this offers a consistent approach
for both.
[Looking
back](https://discord.com/channels/655572317891461132/655578254970716160/1184237511766179840),
this is more or less the second option in that message, but using the
PeekNextIs to avoid vagueness about what's being popped first.
Note I'm putting in PeekNextIs for what I'm hoping will be a pretty
narrow use-case. I could've added depth arguments to the Peek functions,
but that would've rippled through a number of APIs and it's not clear to
me that this has generic utility. I mean, right now it could just be
PeekNextIsVariableInitializer, since it's only optional in that case.
Adds `BindAlias` with a hybrid of `BindName` and `NameRef` semantics. I
think it's slightly closer to `BindName` because it introduces a name,
so I'm going more in that direction. This also matches the need for
`bind_name_id` with imports on enclosing scopes.
Note, only things that look like a name reference are being allowed on
the RHS of `alias`. This includes builtins that look like name
references, such as `bool`, but not ones that turn into values
underneath, such as `false`.
Use two different nodes for "<type> followed by `as`" and "<type>
omitted before `as`, use `self`", so it is easier to determine which
case. Later the second case will push the type id for `self` onto the
node stack, making the two paths more similar.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Elliott KaltandRichard Smith
Dana JansensandJon Ross-Perkins
Geoff Romerandjosh11b
Brymer Meneses
CJ Johnson
czapiga
kshokhin