D arithmetic problem

[davidl]

在 Wed, 03 Jun 2009 10:48:02 +0800，Tim Matthews <tim.matthews7 at gmail.com>  
写道:

> davidl wrote:
>> Following two piece of code demonstrate different behaviors currently.
>>  import std.stdio;
>> void main()
>> {
>>     uint v;
>>     v=31234;
>>     byte t= -1;
>>     v |= t;
>>     writefln(v);
>> }
>>  Output:4294967295
>>  import std.stdio;
>> void main()
>> {
>>     uint v;
>>     v=31234;
>>     byte t= -1;
>>     v |= cast(ubyte)t;
>>     writefln(v);
>> }
>>  Output:31487
>>  I would always want the second result. What's your opinion?
>>
>
> should be in d.learn but try this:
>
> import std.stdio;
> void main()
> {
>      uint v;
>      v=31234;
>      ubyte t= -1;
>      v |= t;
>      writefln(v);
> }

I mean the first behavior can cause problems. I doubt any coder would try  
to get that result by writing that piece of code. I ported some C# source  
to D, and I got this semantic different issue.

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