Introduce a new expression kind, OpenExistentialExpr, that "opens" up
an existential value into a value of a fresh archetype type that
represents the dynamic type of the existential. That value can be
referenced (via an OpaqueValueExpr) within the within the
subexpression of OpenExistentialExpr. For example, a call to a
DynamicSelf method on an existential looks something like this:
(open_existential_expr implicit type='P'
(opaque_value_expr implicit type='opened P' @ 0x7fd95207c290
unique)
(load_expr implicit type='P'
(declref_expr type='@lvalue P' decl=t.(file).func
decl.p@t.swift:5:37 specialized=no))
(erasure_expr implicit type='P'
(call_expr type='opened P'
(archetype_member_ref_expr type='() -> opened P'
decl=t.(file).P.f@t.swift:2:8 [with Self=opened P]
(opaque_value_expr implicit type='opened P' @
0x7fd95207c290 unique))
(tuple_expr type='()')))))
Note that we're using archetype_member_ref_expr rather than
existential_member_ref_expr, because the call is operating on the
opaque_value_expr of archetype type. The outer erasure turns the
archetype value back into an existential value.
The SILGen side of this is somewhat incomplete; we're using
project_existential[_ref] to open the existential, which is almost
correct: it gives us access to the value as an archetype, but IRGen
doesn't know to treat the archetype type as a fresh archetype whose
conformances come from the existential. Additionally, the output of
the opened type is not properly parsable. I'll fix this in follow-on
commits.
Finally, the type checker very narrowly introduces support for
OpenExistentialExpr as it pertains to DynamicSelf. However, this can
generalize to support all accesses into existentials, eliminating the
need for ExistentialMemberRef and ExistentialSubscript in the AST and
protocol_method in SIL, as well as enabling more advanced existential
features should we want them later.
Swift SVN r13740
function. Parse inout as a contextual keyword there, shoving it into the
TypedPattern (instead of introducing a new kind of Pattern). This enables
us to parse, sema, and irgen the new '@-less' syntax for inout.
Swift SVN r13559
with FuncDecls. This allows us to eliminate special case code for handling
self in various parts of the compiler.
This also improves loc info (debug info and AST info) because 'self' now
has a location instead of being invalid.
I also took the opportunity to factor a bunch of places creating self decls
to use similar patterns and less copy and paste code.
Swift SVN r13196
Allow IfStmts and WhileStmts to have as their condition either an expression, as usual, or a pattern binding introduced by 'var' or 'let', which will conditionally bind to the value inside an optional. Unlike normal pattern bindings, these bindings require an in-line initializer, which will be required to be Optional type. Parse variable bindings in this position, and type-check them by requiring an Optional on the right-hand side and unwrapping it to form the pattern type. Extend SILGen's lowering of if and while statements to handle conditionally binding variables.
Swift SVN r13146
they haven't been deserialized yet.
If a specific ASTWalker subclass doesn't care about the members then it should just skip walking them.
Swift SVN r12722
This still isn't /that/ lazy because a lot of things can force member
deserialization (such as the type-checker generating a DestructorDecl for
every imported class), and we don't do this in a member-granular way just
yet. I don't see any change in testing time, for example.
But besides just being a good thing in general, this perturbs the order
of imported decls enough to fix <rdar://problem/15799697>: we can now
reliably see that there is a -URL:something: function on NSObject that
blocks any properties named 'URL' from being imported as properties.
(Which we don't actually want; see <rdar://problem/15456130>.)
Swift SVN r12685
A few places in the core compiler were referring to instances of the
Sequence protocol as "Containers". The "Indexable" protocol will soon
be renamed "Container," so eliminate this potential confusion
Swift SVN r11944
Change Pattern::getBoundName to look through VarPatterns,
which means that the presence of var/let in an argument list no longer
change the mangling of the function.
Swift SVN r11780
This allows expressions such as ".foo" and ".foo(1)" to refer to
static variables and static methods, respectively, as well as enum
cases.
To get here, rework the parsing of delayed identifier expressions a
bit, so that the argument itself is part of the delayed argument
expression rather than a separate call expression. This simplifies
both the handling of patterns of this form and the type checker, which
can now user simpler constraints.
If we really want to support (.foo)(1), we can make that work, but it
seems unnecessary and perhaps confusing.
Swift SVN r10626
Eliminate the annoying, rarely-firing "while converting 'var' initial
value to declared type" note. We'll eventually have better ways to
deal with this. Otherwise, no functionality change.
Swift SVN r9677
As with the monadic '?', we treat any left-bound '!' as a postfix
operator. Currently, it extracts the value of its optional
subexpression, failing at run-time if the optional is empty.
Swift SVN r8948
Parse '_' as a DiscardAssignmentExpr. Type-check it as an lvalue, and check that it only appears in the LHS of AssignExprs. During matching pattern resolution, convert it into an AnyPattern. In SILGen, when we see '_' in the LHS of an assignment, ignore the corresponding RHS rvalue.
Swift SVN r8848
Require that either T be default constructible or that the user provide a closure that maps indices to initial values. We don't actually call the closure yet to initialize the array; that's blocked on function abstraction difference <rdar://problem/13251236>.
Swift SVN r8801
Instead of relying on the subpattern being a well-formed TuplePattern, let's track our own subelements so we can associate them to properties and validate them ourselves.
Swift SVN r8771
As suggested by Dmitri, walk the expr so that clients such as syntax highlighting can see it, but discard the result if it doesn't come back as a LiteralExpr to avoid breaking the invariant.
Swift SVN r8573
Implement the new rules for mapping between selector names and
constructors. The selector for a given constructor is formed by
looking at the names of the constructor parameters:
* For the first parameter, prepend "init" to the parameter name and
uppercase the first letter of the parameter name. Append ':' if
there are > 1 parameters or the parameter has non-empty-tuple type.
* For the remaining parameters, the name of each parameter followed
by ':'.
When a parameter doesn't exist, assume that the parameter name is the
empty string.
And, because I failed to commit it separately, support selector-style
declarations of constructor parameters so that we can actually write
constructors nicely, e.g.:
// selector is initWithFoo:bar:
constructor withFoo(foo : Foo) bar(bar : Bar) { ... }
Swift SVN r8361
AnyFunctionRef is a universal function reference that can wrap all AST nodes
that represent functions and exposes a common interface to them. Use it in two
places in SIL where CapturingExpr was used previously.
AnyFunctionRef allows further simplifications in other places, but these will
be done separately.
Swift SVN r8239