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From: "Mattias Lundstr�m" <ehsmalu@ehpt.com>
Subject: Re: Software landmines (loops)
Date: 1998/09/02
Message-ID: <35ED51F3.DB7ADAD9@ehpt.com>#1/1
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Date: 1998-09-02T00:00:00+00:00
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Richard Jones wrote:
> Both of you miss the point that exceptions solve this problem
> neatly and naturally, i.e. in some sort of bastardized
> Java/C++ hybrid you might write:
> 
>     File f ("name", File::OpenReadOnly);
>     while (...) {
> 
>       if (error_condition) throw new ErrorException;
>     }
>     return;
> 
> Rich.

Not so. This is equivalent (if only function scope is
considered here):

    File f ("name", File::OpenReadOnly);
    while (...) {
      if (error_condition) return NOT_OK;
    }
    return OK;

which depends on the File object to do the cleanup in
its destructor. This is one way to solve the problem, but
it has nothing to do with the whole exception vs return
code discussion.

Note also that in the case of Java this kind of resource
cleanup may not be satisfactory since we can not know when
the finalization (cleanup) is actually done.

- Mattias