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From: dmitry@elros.cbb-automation.de (Dmitry A. Kazakov)
Newsgroups: comp.lang.ada
Subject: Re: Why not using [] instead of () for array?
Date: Wed, 27 Feb 2002 08:48:18 GMT
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Date: 2002-02-27T08:48:18+00:00
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On 26 Feb 2002 20:54:03 -0800, dewar@gnat.com (Robert Dewar) wrote:

>Toshitaka Kumano <kumano@cl.cilas.net> wrote in message news:<3C7A8668.50BC257B@cl.cilas.net>...
>
>> From a mathematical view, The syntax,
>>    Output := Mapping (Input);  
>> can be read "Input maps onto Input".
>
>Kumano-san states the mathematical argument very nicely
>here. Personally I tend to agree with this point of view.

Yes, however analogy is not complete in Ada. At least three things
spoil this nice equivalence. For arrays one can do:

1. Result assignment.  Mapping (Input) := Output

2. Index ranges. Subset := Mapping (From..To)

3. Aggregates

This by no means invalidates the argument of course. Rather opposite,
one should support access results, user-defined index types (=>ranges,
slices), user-defined aggregates ...

... and maybe user-defined []-operator (:-))

Regards,
Dmitry Kazakov