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From: "(see below)" <yaldnif.w@blueyonder.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: Avoiding side effects
Date: Tue, 07 Oct 2008 15:51:44 +0100
Message-ID: <C5113610.FB781%yaldnif.w@blueyonder.co.uk>
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Date: 2008-10-07T15:51:44+01:00
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On 07/10/2008 15:47, in article uprmc4g3i.fsf@no.email.thanks.invalid,
"Anders Wirzenius" <anders@no.email.thanks.invalid> wrote:

> "(see below)" <yaldnif.w@blueyonder.co.uk> writes:
> 
>> On 07/10/2008 12:08, in article wvbrfxn8hdc7.fsf@sun.com, "Ole-Hjalmar
>> Kristensen" <ole-hjalmar.kristensen@substitute_employer_here.com> wrote:
>> 
>>> Yes, I think any program which use a read/write interface to a file
>>> will have side effects in that sense. The only way I can think of for
>>> avoiding this would be to mmap the whole file, then it will appear as
>>> an array of bytes.
>> 
>> Why would stepping through an array not be thought a "side" effect?
> 
> A function that returns the row of that array and only that
> would perhaps be a function without side effects. The information
> in that row can be fetched when needed.

A function that always returns the same row of an array would be of little
use, I should think.

-- 
Bill Findlay
<surname><forename> chez blueyonder.co.uk