A lot of files transitively include Expr.h, because it was
included from SILInstruction.h, SILLocation.h and SILDeclRef.h.
However in reality most of these files don't do anything
with Exprs, especially not anything in IRGen or the SILOptimizer.
Now we're down to 171 files in the frontend which depend on
Expr.h, which is still a lot but much better than before.
In Swift 4 mode, no longer consider e.g. 'nsNumber as Int' or 'nsValue as NSRange' to be valid coercions. This would break compatibility with Swift 3, so in Swift 3 mode, accept the coercion, but *also* accept a checked cast without a warning, and raise a migration warning about the unchecked coercion.
Previously, bridging conversions were handled as a form of "explicit
conversion" that was treated along the same path as normal
conversions in matchTypes(). Historically, this made some
sense---bridging was just another form of conversion---however, Swift
now separates out bridging into a different kind of conversion that is
available only via an explicit "as". This change accomplishes a few
things:
* Improves type inference around "as" coercions. We were incorrectly
inferring type variables of the "x" in "x as T" in cases where a
bridging conversion was expected, which cause some type inference
failures (e.g., the SR-3319 regression).
* Detangles checking for bridging conversions from other conversions,
so it's easier to isolate when we're applying a bridging
conversion.
* Explicitly handle optionals when dealing with bridging conversions,
addressing a number of problems with incorrect diagnostics, e.g.,
complains about "unrelated type" cast failures that would succeed at
runtime.
Addresses rdar://problem/29496775 / SR-3319 / SR-2365.
- The DeclContext versions of these methods have equivalents
on the DeclContext class; use them instead.
- The GenericEnvironment versions of these methods are now
static methods on the GenericEnvironment class. Note that
these are not made redundant by the instance methods on
GenericEnvironment, since the static methods can also be
called with a null GenericEnvironment, in which case they
just assert that the type is fully concrete.
- Remove some unnecessary #includes of ArchetypeBuilder.h
and GenericEnvironment.h. Now changes to these files
result in a lot less recompilation.
The ASTContext-level map of delayed pattern contexts is a DenseMap
that could get reallocated by lazy deserialization of generic
environments. Don't re-use an iterator across the potential lazy
deserialization.
When a pattern within a type context is serialized, serialize its
interface type (not its contextual type). When deserializing, record
the interface type and keep a side table of the associated
DeclContext, so that we can lazily map to the contextual type on first
access. This is designed to break recursion when we change the way
archetypes and generic environments are serialized.
Fixes SR-1050, where @NSManaged subpatterns were not yet visited, and
thus still were deemed 'stored', by the time getStorage() was called
on the whole pattern. Change this to check the subpattern storage as
we go. Test case added.
This class formalizes the common case of the "trailing allocation" idiom we use
frequently. I didn't spot any true bugs while making this change, but I did see
places where we were using the wrong pointer type or casting through void* for
no good reason. This will keep us honest.
I'll get to the other libraries soon.
Parameters (to methods, initializers, accessors, subscripts, etc) have always been represented
as Pattern's (of a particular sort), stemming from an early design direction that was abandoned.
Being built on top of patterns leads to patterns being overly complicated (e.g. tuple patterns
have to have varargs and default parameters) and make working on parameter lists complicated
and error prone. This might have been ok in 2015, but there is no way we can live like this in
2016.
Instead of using Patterns, carve out a new ParameterList and Parameter type to represent all the
parameter specific stuff. This simplifies many things and allows a lot of simplifications.
Unfortunately, I wasn't able to do this very incrementally, so this is a huge patch. The good
news is that it erases a ton of code, and the technical debt that went with it. Ignoring test
suite changes, we have:
77 files changed, 2359 insertions(+), 3221 deletions(-)
This patch also makes a bunch of wierd things dead, but I'll sweep those out in follow-on
patches.
Fixes <rdar://problem/22846558> No code completions in Foo( when Foo has error type
Fixes <rdar://problem/24026538> Slight regression in generated header, which I filed to go with 3a23d75.
Fixes an overloading bug involving default arguments and curried functions (see the diff to
Constraints/diagnostics.swift, which we now correctly accept).
Fixes cases where problems with parameters would get emitted multiple times, e.g. in the
test/Parse/subscripting.swift testcase.
The source range for ParamDecl now includes its type, which permutes some of the IDE / SourceModel tests
(for the better, I think).
Eliminates the bogus "type annotation missing in pattern" error message when a type isn't
specified for a parameter (see test/decl/func/functions.swift).
This now consistently parenthesizes argument lists in function types, which leads to many diffs in the
SILGen tests among others.
This does break the "sibling indentation" test in SourceKit/CodeFormat/indent-sibling.swift, and
I haven't been able to figure it out. Given that this is experimental functionality anyway,
I'm just XFAILing the test for now. i'll look at it separately from this mongo diff.
is used by precisely one thing (producing a warning in a scenario that is obsolete
because we deprecated the entire thing), so the complexity isn't worth it anymore.
Requiring a variadic parameter to come at the end of the parameter
list is an old restriction that makes no sense nowadays, and which we
had all thought we had already lifted. It made variadic parameters
unusable with trailing closures or defaulted arguments, and made our
new print() design unimplementable.
Remove this restriction, replacing it with a less onerous and slightly
less silly restriction that we not have more than one variadic
parameter in a given parameter clause. Fixes rdar://problem/20127197.
Swift SVN r30542
- Enable 'catch is NSError' and 'catch let e as NSError {' patterns to
a) work, and b) be considered to be exhaustive catches. This enables
people to catch an error and *use* it as an NSError directly, instead
of having to do boiler-platey cases. This is particularly important
for the migrator.
- Do not warn about non-noop coersion casts (like "_ as NSError" when
matching an ErrorType), since they provide useful type adjustment to
the subpattern. Still warn on noop ones.
- Simplify CatchStmt::isSyntacticallyExhaustive to use
Pattern::isRefutablePattern. Add a FIXME, because the parser is guiding
closure "throws" inference before the pattern is type checked, which means
that it is incorrect (but only in subtle cases).
- When diagnosing pointless 'as' patterns like:
switch 4 {
case _ as Int: break
say "'as' test is always true" instead of "'is' test is always true".
Swift SVN r28774
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
to represent them, and just dropped them on the ground. Now we parse them,
persist them in the AST, and "resolve" them from the expr grammar, but still
drop them on the ground. This is progress towards fixing: rdar://20135489
Swift SVN r26828
to find variables, enabling it to work with refutable patterns in
addition to nonrefutable ones. This allows eliminating some special
case code in the parser, NFC.
Swift SVN r26686
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 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
Curried function parameters (i.e., those past the first written
parameter list) default to having argument labels (which they always
have), but any attempt to change or remove the argument labels would
fail. Use the fact that we keep both the argument labels and the
parameter names in patterns to generalize our handling of argument
labels to address this problem.
The IDE changes are due to some positive fallout from this change: we
were using the body parameters as labels in code completions for
subscript operations, which was annoying and wrong.
Fixes rdar://problem/17237268.
Swift SVN r24525
type-checking and applying attributes.
We should really move to a model where variables are
type-checked in a single pass, including their attributes.
However, given that we don't, attributes which affect the
type must be applied in multiple places and hence multiple
times to the same declaration.
Swift SVN r16339
Parse the new function syntax, which allows both the argument (API)
and parameter (internal) name to be specified prior to the colon
within each parameter. Don't re-use the existing pattern-parsing
logic. Rather, implement a new (far simpler) parser for this purpose,
then map from its simple data structures to ArgParams and BodyParams
as we're used to.
There are a number of caveats here:
- We no longer have the ability to use patterns for parameters in
function declarations. The only place this really has an impact is
that it makes the ~> hack in the standard library even uglier.
- This exposed some issues with code completion with generic
parameters that need to be investigated.
- There's still some work to be done to improve recovery when things
parse poorly within a parameter list; there are some XFAILs to deal
with that.
I'll address the last two issues with follow-up commits.
Swift SVN r15967
Allow a form of 'case is T' that matches the cast result to a subpattern, 'case <pattern> as T'. This exposes an issue in switch destructuring with casting into complex class hierarchies <rdar://problem/16401831> but works for common cases.
Swift SVN r15396
Previously, we were cloning the default arguments completely, which
meant code duplication (when inheriting within a module) or simply a
failure (when inheriting across modules). Now, we reference the
default arguments where we inherited them, eliminating the
duplication. Part of <rdar://problem/16318855>.
Swift SVN r15062
