help-gnu-emacs
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: binding b-key to pageback behavior


From: Emanuel Berg
Subject: Re: binding b-key to pageback behavior
Date: Thu, 28 Nov 2019 07:34:00 +0100
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux)

VanL wrote:

>> Absolutely, but you still need to mention
>> the individual modes (or maps) and whenever
>> the scrolling stuff differs, that has to be
>> explicit as well. So ultimately the result
>> of doing that wouldn't be all that different
>> from setting it up mode by mode.
>
> In a more perfect world DWIM Mode just works.

But it works sort of like that if only modes
were to stick to the standard every-Emacs
stuff. When they don't most likely it means
they have reasons not to. And when that happens
it must be mentioned somewhere if you want to
configure it. If they didn't do it, do it
yourself VanL :)

> C17's draft N2176 page 13 point 14 is an
> unpleasant shocker.

    14 EXAMPLE 5 Rearrangement for
    floating-point expressions is often
    restricted because of limitations in
    precision as well as range.
    The implementation cannot generally apply
    the mathematical associative rules for
    addition or multiplication, nor the
    distributive rule, because of roundoff
    error, even in the absence of overflow and
    underflow. Likewise, implementations cannot
    generally replace decimal constants in
    order to rearrange expressions. In the
    following fragment, rearrangements
    suggested by mathematical rules for real
    numbers are often not valid (see F.9).

    double x, y, z;
    /* ... */
    x = (x * y) * z; // not equivalent to x *= y * z;
    z = (x - y) + y; // not equivalent to z = x;
    z = x + x * y;   // not equivalent to z = x * (1.0 + y);
    y = x / 5.0;     // not equivalent to y = x * 0.2;


Don't download this:
  http://www2.open-std.org/JTC1/SC22/WG14/www/abq/c17_updated_proposed_fdis.pdf

-- 
underground experts united
http://user.it.uu.se/~embe8573
https://dataswamp.org/~incal




reply via email to

[Prev in Thread] Current Thread [Next in Thread]