Previously some parts of the compiler referred to them as "fields",
and most referred to them as "elements". Use the more generic 'elements'
nomenclature because that's what we refer to other things in the compiler
(e.g. the elements of a bracestmt).
At the same time, make the API better by providing "getElement" consistently
and using it, instead of getElements()[i].
NFC.
Swift SVN r26894
This patch introduces a new kind of pattern for matching bool literals, i.e. true and false. Essentially, it is very similar to a pattern for matching enum elements, but simpler. Most of the code is just a boiler plate code copy/pasted from the code for enum element patterns. The only different thing is the emitBoolDispatch function, which emits a SIL code for matching bools.
With this patch, we don't get any false non-exhaustive switch diagnostics for switches on bools anymore. And we have a lot of radars complaining about it. For example rdar://16514545 and rdar://20130240.
Note, that this patch fixes the non-exhaustive switch diagnostics without changing the internal representation of bools. Implementing bool as an enum would have the same effect when it comes to these diagnostics and we would get this diagnostics fix for free, i.e. without any code committed here. But implementing bools-as-enums is an ongoing work and I'm investigating its performance implications. If we become confident that bool-as-enum does not have a negative impact on performance and decide to merge it, then we can revert this patch as it would not be necessary anymore. But if we decide to skip the enum-as-bool approach to its performance issues, then we would have at least fixed the false non-exhaustive diagnostics for bools by means of this patch.
Swift SVN r26650
This patch also introduces some SILGen infrastructure for
dividing the function into "ordinary" and "postmatter"
sections, with error-handling-like stuff going into the
final section. Currently, this is largely undermined by
SILBuilder, but I'm going to fix that in a follow-up.
Swift SVN r26422
Previously, a multi-pattern var/let decl like:
var x = 4, y = 17
would produce two pattern binding decls (one for x=4 one for y=17). This is convenient
in some ways, but is bad for source reproducibility from the ASTs (see, e.g. the improvements
in test/IDE/structure.swift and test/decl/inherit/initializer.swift).
The hardest part of this change was to get parseDeclVar to set up the AST in a way
compatible with our existing assumptions. I ended up with an approach that forms PBDs in
more erroneous cases than before. One downside of this is that we now produce a spurious
"type annotation missing in pattern"
diagnostic in some cases. I'll take care of that in a follow-on patch.
Swift SVN r26224
If the placeholder is a typed one, parse its type string into a TypeRepr,
resolve it during typechecking and set it as the type for the associated EditorPlaceholderExpr.
Swift SVN r26215
For now, we assume that 'while' after the braces starts
a do/while rather than being an independent statement.
We should disambiguate this, or better, remove do/while.
Tests later.
Swift SVN r26079
We parse 'try' as if it were a unary operator allowed on an
arbitrary element of an expr-sequence, but sequence-folding
constrains it to never appear on the RHS of most operators.
We do allow it on the RHS of an assignment or conditional
operator, but not if there's anything to the right which
was not parsed within the RHS.
We do this for assignments so that
var x = try whatever
and
x = try whatever
both work as you might expect.
We do this for conditionals because it feels natural to
allow 'try' in the center operand, and then disallowing it
in the right operand feels very strange.
In both case, this works largely because these operators are
assumed to be very low-precedence; there are no standard
operators which would parse outside the RHS. But if you
create one and use 'try' before it, we'll diagnose it.
Swift SVN r26052
This introduces a new pattern, spelled "x?" which is sugar for
matching ".Some(x)". It also changes the parser slightly so that
_ (the discard expr) is parsed as a unary expr instead of as an
expr. This allows it to have postfix ? after it, which is important
in pattern contexts to support "case _?:".
Swift SVN r25907
if-let statements (also while and var, of course) that include multiple bindings
and where clauses.
SILGen support still remains, it currently just asserts on the new constructs.
Swift SVN r24239
a capture list hung off the CaptureExpr it was associated with. This made
sense lexically (since a capture list is nested inside of the closure) but
not semantically. Semantically, the capture list initializers are evaluated
outside the closure, the variables are bound to those values, then the closure
captures the newly bound values.
To directly represent this, represent captures with a new CaptureListExpr node,
which contains the ClosureExpr inside of it. This correctly models the semantic
relationship, and makes sure that AST walkers all process the initializers of the
capture list as being *outside* of the closure.
This fixes rdar://19146761 and probably others.
Swift SVN r23756
This commit changes ASTWalker to preserve AbstractFunctionDecl body kinds. When
walking over an AbstractFunctionDecl, ASTWalker calls setBody() on the
declaration to update the body after traversal. Prior to this commit, setBody()
would unconditionally set the body kind to BodyKind::Parsed --- that is,
traversing the AST would change the body kind to Parsed. In some cases, this
modified a body kind from TypeChecked to Parsed, causing a small number of
standard library functions to be type checked twice. This behavior also
interferes with the creation of type refinement contexts for variable accessor
functions (coming in a future commit).
This commit adds an additional parameter to setBody() that allows callers to
provide a body kind (this defaults to Parsed) and changes ASTWalker to preserve
the body kind when walking a AbstractFunctionDecl.
Swift SVN r22607
This patch adds a new 'pound_os' token, a new case for it in parseExprPostfix, and parsing of platform version constraints, e.g., OSX >= 10.10.
It also adds enough type checking and SILGen to get the parsing tests to run without triggering "Unimplemented" assertions.
Swift SVN r21865
This commit adds a new expression (AvailabilityQueryExpr) and a single kind of
specification for when a block of code or function is available
(VersionConstraintAvailabilitySpec). We may add more kinds of specifications
in the future. At the moment, the AvailabilityQueryExpr allows only a
single platform to be queried; I will add support for multiple platforms
in a later commit.
This commit contains just the added AST nodes; no parsing, type checking, etc.
I’ve added assert(false && “Unimplemented”) for places where support for
AvailabilityQueryExpr will need to be added later.
Swift SVN r21760
If either parameter to == has a known concrete type at constraint generation
time, see if that type is a nominal that can derive its conformance to
Equatable. If so, do so, and then add that == to the overload set.
(It may already be there, but that's okay -- it will get uniqued later.)
This isn't perfect because it relies on one of the parameters to == having
a concrete type /before/ constraint solving. There are plenty of reasons
why that wouldn't happen. But this at least fixes the common case, and
breaking the expression up into multiple lines is a less distasteful
workaround than replacing (x == .Value) with !(x != .Value). I've added a
test case that should work but doesn't that we can revisit later.
rdar://problem/18073705
Swift SVN r21557
The eventual goal for extensions of generic types is to require them
to specify their generic parameters, e.g.,
extension Array<T> { ... }
rather than today's
extension Array { ... }
Start parsing (optional) generic parameters here, and update the
representation of ExtensionDecl to accomodate this new grammar
production. Aside from the parser changes, there's no intended
functionality change here.
Swift SVN r20682
We no longer need this language feature. The Sema support is still skeletally kept in place because removing it seems to totally break pointer conversions; I need to work with Joe and Doug to figure out why that's the case.
Swift SVN r19289
Handle parsing of dictionary type sugar into its own type
representation, including both type and expression contexts.
This is the first part of <rdar://problem/17460972>; we still need a
sugared Type node.
Swift SVN r19239
Rather than force conformances to Equatable to be added to all imported enumeration types outright, change them back to being lazily added. We can then handle situations where new overloads of '==' are introduced during constraint generation by re-writing the relevant overload disjunction constraint to include the newly forced declarations as bind options.
Swift SVN r17557
This leaves in the existing syntax for @unchecked T?. That will
be addressed in later patches.
There's still a mysterious case where some of the SIL output
includes UncheckedOptional<T> and some places T!.
Moreover, this doesn't handle SourceKit's behavior for printing
for overrides. This just handles parsing the 'T!' syntax.
Swift SVN r16945
them with uses of TypeExpr instead. The remaining uses of
MetaTypeExpr (which will be renamed soon) are places where we
are applying the ".dynamicType" virtual property to an expression.
Unadorned uses of types in code, e.g. the Int in "Int.self" are
now represented with TypeExpr.
One unfortunate travesty that doing this work revealed is that we
are extremely sloppy and terrible about maintaining location information
in implicitly generated decls, and our invariants vary quite a bit. This
is really horrible, but I'm not sure whether I'll go fix the hacks or not.
This patch perpetuates the existing crimes, but makes them more visible.
NFC!
Swift SVN r16646
when resolving identifiers into types. This will eventually allow us to
solve annoying issues like rdar://15295763&15588967 by better modeling
what we already have.
Swift SVN r16620
Add a third branch to the constraint system for '&x' expressions that allows conversion from an lvalue to a type via an additional writeback step:
- Add an LValueConversionExpr node that converts from @lvalue T to @lvalue U, given a pair of functions that convert T -> U and U -> T, to represent the writeback temporary.
- Allow conversion in an inout expression from @lvalue T to a type U that has the following members:
static func __writeback_conversion(Builtin.RawPointer, T.Type) -> U
static func __writeback_conversion_get(T) -> V
static func __writeback_conversion_set(V) -> T
which builds a solution that produces an LValueConversion from the get/set pair before passing the pointer to the writeback temporary off to the conversion function.
Swift SVN r15764
Language features like erasing concrete metatype
values are also left for the future. Still, baby steps.
The singleton ordinary metatype for existential types
is still potentially useful; we allow it to be written
as P.Protocol.
I've been somewhat cavalier in making code accept
AnyMetatypeType instead of a more specific type, and
it's likely that a number of these places can and
should be more restrictive.
When T is an existential type, parse T.Type as an
ExistentialMetatypeType instead of a MetatypeType.
An existential metatype is the formal type
\exists t:P . (t.Type)
whereas the ordinary metatype is the formal type
(\exists t:P . t).Type
which is singleton. Our inability to express that
difference was leading to an ever-increasing cascade
of hacks where information is shadily passed behind
the scenes in order to make various operations with
static members of protocols work correctly.
This patch takes the first step towards fixing that
by splitting out existential metatypes and giving
them a pointer representation. Eventually, we will
need them to be able to carry protocol witness tables
Swift SVN r15716
Add two new AST node types:
- InOutConversionExpr, which represents an '&x' expression that involves inout conversion. This will be a signal to SILGen not to introduce a writeback scope for the nested conversion call.
- LValueToPointerExpr, which represents the primitive '@lvalue T' to 'RawPointer' conversion that produces the argument to the inout conversion.
Build an InOutConversionExpr AST when an inout expression is resolved by a conversion to an BuiltinInOutAddressConvertible type.
Swift SVN r15594
Factor an IdentityExpr base class out of ParenExpr, and migrate most of the logic to see through ParenExprs to see through IdentityExprs instead. Add DotSelfExpr as a new subclass of IdentityExpr, produced by parsing 'x.self'.
Swift SVN r14381
- Respond to Doug's code review feedback
- Stop hacking around with scopes and use "emplace" to work around RAII in the inactive config case
- Limit use of StringRef on the front-end, in favor of std::string
- Use ArrayRef rather than SmallVector within IfConfigDecl
- Reorder new property declarations on BraceStmt to prevent unnecessary alignment issues
- Update ParseBraceItems to better capture top-level declarations, rather than using token lookahead
Swift SVN r14306
These changes add support for build and target configurations in the compiler.
Build and target configurations, combined with the use of #if/#else/#endif allow
for conditional compilation within declaration and statement contexts.
Build configurations can be passed into the compiler via the new '-D' flag, or
set within the LangOptions class. Target configurations are implicit, and
currently only "os" and "arch" are supported.
Swift SVN r14305
