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From: Victor Porton <porton@narod.ru>
Newsgroups: comp.lang.ada
Subject: Re: Lazy evaluation
Date: Tue, 23 Sep 2014 15:01:29 +0300
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Xref: number.nntp.dca.giganews.com comp.lang.ada:189104
Date: 2014-09-23T15:01:29+03:00
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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.

> Now, let "&" be lazy in the right argument:
> 
>    function "&" (Left : String; Right : lazy String) return String;
> 
> In my opinion, it is not laziness which causes problems, but more the
> closures. If closures were limited in some reasonable (from Ada's POV)
> way, then laziness would be not an issue.

-- 
Victor Porton - http://portonvictor.org