Parameters are normally given 'private' access, because they can only
be referred to within the body of the owning function. However,
single-expression closures allow a parameter to appear in a constraint
system in the containing context. Mark closure parameters as
'fileprivate' instead.
Similarly, 'private' at the top level is normally equivalent to
'fileprivate', but not for a decl that appears within top-level
imperative code, which has a TopLevelCodeDecl context. This currently
only happens for bindings in a top-level 'guard' statement; mark
these variables and constants as 'fileprivate' as well.
More progress on SE-0025 ('private' and 'fileprivate').
Make the following patterns illegal:
if var x = ... {
...
}
guard var x = ... else {
...
}
while var x = ... {
...
}
And provide a replacement fixit 'var' -> 'let'.
rdar://problem/23172698
Swift SVN r32855
Otherwise, we'll fail to capture "locals" declared in top-level guard
statements. This led to an assertion failure in SILGen.
Depends on previous commit.
rdar://problem/21997265
Swift SVN r30812
