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From: Sam <sam@email-scan.com>
Newsgroups: comp.lang.c++
Subject: Re: We have a new standard!
Date: Tue, 07 Jan 2025 21:32:34 -0500
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Chris Ahlstrom writes:

> Muttley@DastardlyHQ.org wrote this post while blinking in Morse code:
>
> > I never understood the point of that. Why not increase the semantic scope
> > of "typedef" instead of having 2 keywords that in a lot of circumstances
> > do the same thing?
>
> Because using is a nicer to read?

I was wondering about that, too. I forget the exact keywords I used when  
searching for the answer, but I did read a convincing argument in favor of  
a using declaration.

This was not the main argument, but there are some things that can be done  
with using that cannot be done with a typedef. For example, using a real- 
life example:

template<typename basedon_t>
using derivedvaluelist=ref<derivedvalueListObj<basedon_t>,
                           derivedvalueListBase<basedon_t>>;

There is no equivalent typedef declaration, for this.

Given that, here's the main argument: if you originally start out with a  
using declaration, instead of a typedef:

using derivedvaluelist=ref<derivedvalueListObj, derivedvalueListBase>;

then, at some point later: going from that, to the template, looks more  
"logical" then replacing a typedef with something else, entirely.

TLDR: the "left" and the "right" side component, of the alias declaration,  
is consistent, versus swapped.