Path: csiph.com!eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail
From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c++
Subject: Re: 1.0 / 0.0
Date: Sun, 16 Jan 2022 12:40:40 -0800
Organization: A noiseless patient Spider
Lines: 17
Message-ID: <86h7a3tnw7.fsf@linuxsc.com>
References: <sqib7m$sth$1@dont-email.me> <sqkrcr$1n51$1@gioia.aioe.org> <d2927e23-ce48-44dc-abb9-3b77b784bae2n@googlegroups.com> <sqkvnt$1t7e$1@gioia.aioe.org> <sqmlqt$1vhs$1@gioia.aioe.org> <sqnf01$1hn9$1@gioia.aioe.org> <squ4m0$258$1@gioia.aioe.org> <squb43$2oi$1@redfloyd.dont-email.me> <sqvsgu$t98$1@gioia.aioe.org> <sr10qc$mae$2@gioia.aioe.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Injection-Info: reader02.eternal-september.org; posting-host="66ee21d996f56235c8cdb5e1ea47e716"; logging-data="1917"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX19kpX+kuiL4+XexxltU5zxaAsp2qQ88k2c="
User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.4 (gnu/linux)
Cancel-Lock: sha1:sqq5ZFf4tRI7jrMJYqhhYHorpk0= sha1:0OIgyinI0S3/cZ/X99MVgPI1hIY=
Xref: csiph.com comp.lang.c++:82787

Juha Nieminen <nospam@thanks.invalid> writes:

> Manfred <noname@add.invalid> wrote:
>
>> The irony is that this is probably one of those examples where C beats
>> C++ - good ol' HUGE_VALF or INFINITE would raise no question at all!
>
> What is the type of INFINITE?  What if you want it as one of the other two
> floating point types?  (Is casting defined in this case?)

I haven't checked the C++ standard, but in C (assuming a suitable
infinite value is available) the macro INFINITY expands to a
constant expression of type float, with an infinite value.  Any
value of type float must have corresponding values in type double
and long double, and converting a float value to double or long
double must produce the corresponding value in the target type.
(Converting includes but is not limited to cast operations.)