Why Java does the compound operator conversion (once again)

Hello to all,
can anyone repeat for me the motivation, why the early Java Language designers introduced the narrowing conversion into the compound operators? (E1 op = E2 is
equivalent to E1 = (T )((E1) op (E2)), where T is the type of E1, except that E1 is evaluated only once)
I can pretty well understand the reasons, why it cannot be changed any more (it is an incompatible change - http://bugs.sun.com/view_bug.do;jsessionid=67cacbc1afced76921b2264b6fd9c?bug_id=4655168). But I cannot see the reason, why to introduce it at the first place.
Thanks a lot for any answer.
Edited by: gree on 13.4.2010 12:33

I never told, I do not like that.You raised Occam's razor, which is the principle that entities should not be multiplied needlessly. If you don't consider it a needless multiplication of entities why introduce it?
According to you answer, I presume ...I stated my view explicitly. No need for you to presume anything.

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