Exception chaining and collectException

[Walter Bright via Digitalmars-d]

Chained exceptions are a good idea, but are more or less a disaster:

1. No other language does chained exceptions

2. Attempting to hammer D chained exceptions into other language schemes (such 
as C++) makes for lots of unfun hours attempting to decode undocumented behavior 
in those other schemes

3. Makes D exceptions incompatible with other language exceptions and their 
infrastructure

4. Are incomprehensibly implemented (I defy anyone to explain how the test cases 
in the test suite are actually supposed to work)

5. Are more or less incompatible with non-GC memory allocation

I'd like to remove them from D.

I recommend *not* designing any program that requires them.