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NNTP-Posting-Date: Tue, 07 Oct 2008 06:08:42 -0500
Newsgroups: comp.lang.ada
Subject: Re: Avoiding side effects
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From: Ole-Hjalmar Kristensen
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Organization: Sun Microsystems
Date: 07 Oct 2008 13:08:40 +0200
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Date: 2008-10-07T13:08:40+02:00
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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.

>>>>> "AW" == Anders Wirzenius <anders@no.email.thanks.invalid> writes:

<snip>

    AW> Thanks for that, too. The program I wrote did the job and was
    AW> sufficiently fast. My question was more about how to do it using
    AW> subprograms (functions) without side effects. 
    AW> I suppose "Process records from..." and "Process tail..." are
    AW> having side effects if coded as subprograms, as they advance the
    AW> pointer in the two files.

    AW> -- 
    AW> Anders

-- 
   C++: The power, elegance and simplicity of a hand grenade.