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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c++
Subject: Re: Static_assert in 2017 C++
Date: Sun, 01 Sep 2019 20:48:28 -0700
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woodbrian77@gmail.com writes:
> I have this line
> static_assert(::std::numeric_limits<float>::is_iec559,"Only IEEE754 supported");
>
> in my library: https://github.com/Ebenezer-group/onwards
>
> .  I wrote that line when I was using 2011 C++ and the comment
> was required.  Now I require 2017 C++ and am trying to decide between:
>
> a. remove the comment
> b. reduce the comment to just "IEEE754", or
> c. leave it as it is.

The issue is that in C++11 and earlier, static_assert requires
a second argument (which is *not* a "comment"), and in C++17 and later
it does not.

Given what you have, I can't think of any good reason not to leave it as
it is.

If you do drop the message argument, your code will no longer
compile with a pre-2017 C++. implementation (unless it supports a
single-argument static_assert as an extension).  If it won't anyway
for other reasons, that probably doesn't matter.

What advantage do you see from removing or changing the message
argument?

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */