[Fwd: Part 28 -> Part 11 issue]

[Ed Barkmeyer]

Wilson, Peter R wrote:

>     I must be missing something here. It has always been possible to do this:
> ENTITY ent;
>   low : INTEGER;
>   high : INTEGER;
>   arr : ARRAY[low:high] OF INTEGER;
> -- and similarly for the other aggregates
> -- WHERE
> -- wr1 : low <= high; -- may or may not be specified
> END_ENTITY;
> 
>     The array bounds cannot be known until runtime as the depend on values in any particular instance. 

No, Peter, you didn't miss anything.  I did.
We just assumed that it would be possible to determine the sizes of ARRAY 
aggregation types at "compile-time".  Since that is false, it follows that the 
Part 28 mapping has to make a special case for bounds that are literals, and 
treat all other ARRAYs as LIST [0:?].  There is no requirement for an EXPRESS 
tool to do better than that.

Thanks,
-Ed

-- 
Edward J. Barkmeyer                        Email: edbark at nist.gov
National Institute of Standards & Technology
Manufacturing Systems Integration Division
100 Bureau Drive, Stop 8264                Tel: +1 301-975-3528
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