220 38930 <49cde8d1-312f-4c4c-a26e-91bbb1c56a2d@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: mihailnajdenov@gmail.com Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Allow forward class declarations to match a type alias. 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I used the=20 > proposed solution but it unfortunately had me change the forward=20 > declarations of FloatImage.=20 What solution did you use?=20 Did you try the concrete class solution - it is not as na=C3=AFve as it sou= nds,=20 not as hard as it sounds (in C++11+) and has many protentional side=20 benefits. Otherwise the classical solution is not to forward declare a class but to= =20 have xxxfrw.h header instead, where you can put all "leakage of=20 implementation detail".=20 --=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/49cde8d1-312f-4c4c-a26e-91bbb1c56a2d%40isocpp.or= g. ------=_Part_2808_1546498443.1530345151067 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Saturday, June 30, 2018 at 9:49:52 AM UTC+3, Be= ngt Gustafsson wrote:
I got one= good answer: it is not possible due to name mangling having to know that F= loatImage will resolve to a template instance. I used the proposed solution= but it unfortunately had me change the forward declarations of FloatImage.=

=C2=A0What solution did you use?=C2=A0
Did you try the concrete class solution - it is not as na=C3=AFve a= s it sounds, not as hard as it sounds (in C++11+) and has many protentional= side benefits.

Otherwise the classical soluti= on is not to forward declare a class but to have xxxfrw.h header instead, w= here you can put all "leakage of implementation detail".=C2=A0

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To view this discussion on the web visit https://groups.google.= com/a/isocpp.org/d/msgid/std-proposals/49cde8d1-312f-4c4c-a26e-91bbb1c56a2d= %40isocpp.org.
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