operator(s) << are member functions. Why?

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Article #2150

#2150

From: Martin Prange
Date: Mon, 09 Oct 1995 15:46

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To make the operator(s) << (from iostream.h) usable by other classes,
they must be derived by the appropriate iostream-class.
 
As non-member functions they could be used by any class, 
that could be casted to (ostream&) by means of e.g. operator ostream&.
( Which is, what I actually wanted to. )
 
So, the question is:
Why are these operators declared (and implemented , of course), as members ?
Are there design issues I`ve been missing so far?
 
--
 Martin Prange / Member of ALMAP Team / ALCATEL +49 030 3120 
 just alcanet: prange@sel.bln.alcatel.de else @cs.tu-berlin.de
 If you believe, the opinions expressed here are mine - you got it

[ comp.std.c++ is moderated.  Submission address: std-c++@ncar.ucar.edu.
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From: prange@slbh08.bln.sel.alcatel.de (Martin Prange)
Newsgroups: comp.std.c++
Subject: operator(s) << are member functions. Why?
Date: 9 Oct 1995 15:46:35 GMT
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