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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Lazy evaluation
Date: Tue, 23 Sep 2014 21:12:57 +0200
Organization: cbb software GmbH
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Date: 2014-09-23T21:12:57+02:00
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On Tue, 23 Sep 2014 15:01:29 +0300, Victor Porton wrote:

> Dmitry A. Kazakov wrote:
> 
>> Consider the problem of evaluation order:
>> 
>>    X : String := String'Input (File) & String'Input (File); -- Ill
>>    defined!
> 
> I don't understand why it's ill defined. Please explain.

If the stream contains "a" followed by "b", X can be "ab" or "ba" depending
on the evaluation order of arguments.

Compare it with

   expr1 and expr2    vs.   expr1 and then expr2

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de