A DWS 2.2 preview zip [1] (199 kB) has been posted, it is an SVN snapshot, and features recent additions to DWS:
- Contracts are now partially supported: ensure, require and old are available and use the same syntax as Prism contracts [2], inheritance is supported, class invariants are not in just yet, mostly for syntax indecision reasons, see this [3] thread.
- the implies operator is now supported, “a implies b” is equivalent to “(not a) or b”, or in other words, it is false only if a is true and b is false.
- Assert() is supported, and will trigger EAssertionFailed in case of, well, an assertion failure. A compiler option has been added to control the generation of assertions.
- Exception now has a StackTrace method, which will return a textual stacktrace script-side. Runtime errors now also include a stack trace, and new Delphi-side methods provide access to even more details.
- the in operator has been extended to allow class overloading, f.i. you can now use “if (aString in someStringList) then…”, the not in form is also supported.
A fair chunk of the error and exception code has been refactored, if you were relying on it, all the preexisting functionality is still there, though it has been shuffled around to (hopefully) more relevant locations.