From:	NOSPAMsl AT psycode DOT com (Gili)
Newsgroups:	gnu.gcc.help,comp.os.os2.programmer.misc,comp.os.msdos.djgpp
Subject:	Re: C++ constructor problem solved!! Read how, it might come in useful in your future programs!
Date:	20 Jan 1998 02:07:01 GMT
Organization:	Generation.NET
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References:	<bWLoegW7sFse-pn2-bxyqvlUyVUyY AT localhost> <34C2817A DOT 5547BE86 AT alcyone DOT com>
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To:	djgpp AT delorie DOT com
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On Sun, 18 Jan 1998 22:26:02, Erik Max Francis <max AT alcyone DOT com> 
wrote:

> Explicitly calling constructors is dangerous.  Here what's _really_
> happening is that the fstream is being constructed with the default
> constructor, and _then_ you're explicitly calling a nondefault
> constructor.  That is, it's functionally precisely the same thing as:
> 
>     File::File(...):
>         fstream()
>     {
>         ((fstream *) this)->fstream(...);
>         ...
>     }

	I found a second (and perhaps better) way of doing this. Now I use 
"this->fstream.fstream(<parameters>".

>     class File
>     {
>       public:
>         fstream *fs;
> 
>         File(...);
>         ...
>     };
> 
>     File::File(...)
>     {
>         fs = new fstream(...);
>         ...
>     }
> 

	This is unacceptable because I wanted to publicly inherite fstream().
I could use delegation like this but then I won't be inheriting the 
methods and variables of fstream().. Once again, I think 
"this->fstream.fstream()" is a good solution.

Gili

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