in the classification of template names and using declarations. We now
properly typo-correct the leading identifiers in statements to types,
templates, values, etc. As an added bonus, this reduces the number of
lookups required for disambiguation.
llvm-svn: 130288
looking at the context and the correction and using a custom
diagnostic. Also, enable some Fix-It tests that were somewhat lamely
disabled.
llvm-svn: 130283
performs name lookup for an identifier and resolves it to a
type/expression/template/etc. in the same step. This scheme is
intended to improve both performance (by reducing the number of
redundant name lookups for a given identifier token) and error
recovery (by giving Sema a chance to correct type names before the
parser has decided that the identifier isn't a type name). For
example, this allows us to properly typo-correct type names at the
beginning of a statement:
t.c:6:3: error: use of undeclared identifier 'integer'; did you mean
'Integer'?
integer *i = 0;
^~~~~~~
Integer
t.c:1:13: note: 'Integer' declared here
typedef int Integer;
^
Previously, we wouldn't give a Fix-It because the typo correction
occurred after the parser had checked whether "integer" was a type
name (via Sema::getTypeName(), which isn't allowed to typo-correct)
and therefore decided to parse "integer * i = 0" as an expression. By
typo-correcting earlier, we typo-correct to the type name Integer and
parse this as a declaration.
Moreover, in this context, we can also typo-correct identifiers to
keywords, e.g.,
t.c:7:3: error: use of undeclared identifier 'vid'; did you mean
'void'?
vid *p = i;
^~~
void
and recover appropriately.
Note that this is very much a work-in-progress. The new
Sema::ClassifyName is only used for expression-or-declaration
disambiguation in C at the statement level. The next steps will be to
make this work for the same disambiguation in C++ (where
functional-style casts make some trouble), then push it
further into the parser to eliminate more redundant name lookups.
Fixes <rdar://problem/7963833> for C and starts us down the path of
<rdar://problem/8172000>.
llvm-svn: 130082
typo. This can happen with context-sensitive keywords like "super",
when typo correction didn't know that "super" wasn't permitted in this
context.
llvm-svn: 117372
we did was an acceptable lookup. If it is, then we can re-use that
lookup result. If it isn't, we have to perform the lookup again. This
is almost surely the cause behind the mysterious typo.m failures on
some builders; we were getting the wrong lookup results returned.
llvm-svn: 116586
of a binary expression, continue on and parse the right-hand side of
the binary expression anyway, but don't call the semantic actions to
type-check. Previously, we would see the error and then, effectively,
skip tokens until the end of the statement.
The result should be more useful recovery, both in the normal case
(we'll actually see errors beyond the first one in a statement), but
it also helps code completion do a much better job, because we do
"real" code completion on the right-hand side of an invalid binary
expression rather than completing with the recovery completion. For
example, given
x = p->y
if there is no variable named "x", we can still complete after the p->
as a member expression. Along the recovery path, we would have
completed after the "->" as if we were in an expression context, which
is mostly useless.
llvm-svn: 114225
sends. These are far trickier than instance messages, because we
typically have something like
NSArray alloc]
where it appears to be a declaration of a variable named "alloc" up
until we see the ']' (or a ':'), and at that point we can't backtrace.
So, we use a combination of syntactic and semantic disambiguation to
treat this as a message send only when the type is an Objective-C type
and it has the syntax of a class message send (which would otherwise
be ill-formed).
llvm-svn: 114057
narrow, almost useless case where we're inside a parenthesized
expression, e.g.,
(NSArray alloc])
The solution to the general case still eludes me.
llvm-svn: 114039
part of parser recovery. For example, given:
a method1:arg];
we detect after parsing the expression "a" that we have the start of a
message send expression. We pretend we've seen a '[' prior to the a,
then parse the remainder as a message send. We'll then give a
diagnostic+fix-it such as:
fixit-objc-message.m:17:3: error: missing '[' at start of message
send expression
a method1:arg];
^
[
The algorithm here is very simple, and always assumes that the open
bracket goes at the beginning of the message send. It also only works
for non-super instance message sends at this time.
llvm-svn: 113968
a simple, quick check to determine whether the expression starting
with '[' can only be an Objective-C message send. If so, don't parse
it as an array subscript expression. This improves recovery for, e.g.,
[a method1]
[a method2]
so that we now produce
t.m:10:13: error: expected ';' after expression
[a method]
^
instead of some mess about expecting ']'.
llvm-svn: 105221
non-function-local declarations with names similar to what the user
typed. For example, this allows us to correct 'supper' to 'super' in
an Objective-C message send, even though the C function 'isupper' has
the same edit distance.
llvm-svn: 104023
consider "super" as a candidate whenever we're parsing an expression
within an Objective-C method in an interface that has a superclass. At
some point, we'd like to give "super" a little edge over non-local
names; that will come later.
llvm-svn: 104022
Chad Rosier