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From: Jacob Sparre Andersen <jacob@jacob-sparre.dk>
Newsgroups: comp.lang.ada
Subject: Re: need help learning Ada for a modula-2 programmer
Date: Thu, 30 Jan 2014 10:05:32 +0100
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2014-01-30T10:05:32+01:00
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Jeffrey Carter wrote:
> On 01/29/2014 01:41 PM, Jacob Sparre Andersen wrote:
>>
>> Generalising the array index beyond type Integer takes up ten lines
>> in my first take on the task.  (Recursion _might_ make it shorter.)
>
> Mine is the same number of lines whether the index is numeric or
> not. 2 of the lines differ to handle non-numeric indices.

I'm curious how you're doing it.  My implementation has one declaration
of a constant (to manage shifts further than one array length) and one
return statement (split over two lines to make it more readable).

The non-numeric index version has another ten lines to make the
mathematical operations used in the return statement work on a
non-numeric index.

Hmmm...  I think I may have figured it out...

Yes.

Converting back and forth between type Index and integers in-line makes
the return statement somewhat less readable. :-(

Using Ada 2012 I can do it with exactly the requested dozen lines (two
of which are blank to improve readability ;-).

Greetings,

Jacob

PS: I'm waiting for the OP to post his/her solution before I'm going to
    post mine.  Please hurry up.
-- 
Never attribute to malice what can adequately be explained by incompetence.