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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: elementary loops
Date: Fri, 26 Jun 2015 08:26:33 -0400
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On 6/26/2015 7:39 AM, Marcel Mueller wrote:
> On 26.06.15 11.26, Andreas Leitgeb wrote:
>>>> { public static void main( final java.lang.String[] args )
>>>>     { short i = -1;
>>>>       int   j = -1;
>>>>       for( int k = 0; k < 65; ++k ){ i >>>= 1; j <<= 32; }
>>
>> The short i is promoted to int, then the MSB ("sign"-bit) zeroed,
>> then converted back to short, where it's still -1
>
> In this case the >>> operator is meaningless for short int and there is
> no option to perform this operation except for emulating the behavior by
> other bit functions or types. The same applies to byte as well.
> Of course, this is only another side effect of the missing unsigned types.
> Is this guaranteed by the language or just implementation defined?

     The former.  The relevant bits of the Java Language Specification
<http://docs.oracle.com/javase/specs/jls/se8/html/index.html> are

     - 15.26.2 "Compound Assignment Operators"

     - 15.19 "Shift Operators"

     - 5.6.1 "Unary Numeric Promotion"

     - 5.1.2 "Widening Primitive Conversion"

     - 15.16 "Cast Expressions" (implied by 15.26.2)

     - 5.1.3 "Narrowing Primitive Conversion"

-- 
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"Don't be afraid of work. Make work afraid of you." -- TLM