assert() and fatalError()
These functions are meant to be used in user code. They are enabled in debug
mode and disabled in release or fast mode.
_precondition() and _preconditionFailure()
These functions are meant to be used in library code to check preconditions at
the api boundry. They are enabled in debug mode (with a verbose message) and
release mode (trap). In fast mode they are disabled.
_debugPrecondition() and _debugPreconditionFailure()
These functions are meant to be used in library code to check preconditions that
are not neccesarily comprehensive for safety (UnsafePointer can be null or an
invalid pointer but we can't check both). They are enabled only in debug mode.
_sanityCheck() and _fatalError()
These are meant to be used for internal consistency checks. They are only
enabled when the library is build with -DSWIFT_STDLIB_INTERNAL_CHECKS=ON.
I modified the code in the standard library to the best of my judgement.
rdar://16477198
Swift SVN r18212
Empty NSArrays are usually represented by emptyNSSwiftArray, whose
element type is irrelevant. So when doing a getObjects:range: on that,
presumably the range's length is zero and we shouldn't do any sanity
checking w.r.t. the element type.
Fixes <rdar://problem/16914909> Assertion failed attempting to append
arrays when subclassing Cocoa class
Swift SVN r18110
Just moving things between files, and creating a few new source files, in
the standard library, so it's easier to find a given component.
Swift SVN r16094
