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How can I get the type in a C++17 fold function?

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  How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 09:48 +0000
    Re: How can I get the type in a C++17 fold function? Juha Nieminen <nospam@thanks.invalid> - 2022-12-08 12:18 +0000
      Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 15:41 +0000
        Re: How can I get the type in a C++17 fold function? Juha Nieminen <nospam@thanks.invalid> - 2022-12-09 12:57 +0000
    Re: How can I get the type in a C++17 fold function? Öö Tiib <ootiib@hot.ee> - 2022-12-08 04:45 -0800
      Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 15:45 +0000
        Re: How can I get the type in a C++17 fold function? Öö Tiib <ootiib@hot.ee> - 2022-12-08 13:59 -0800
    Re: How can I get the type in a C++17 fold function? Vir Campestris <vir.campestris@invalid.invalid> - 2022-12-14 10:42 +0000
    Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-14 18:02 +0100
      Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-14 17:17 +0000
        Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-14 18:23 +0100
    Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-15 17:59 +0100
      Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-15 17:20 +0000
        Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-15 18:37 +0100
      Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 05:26 +0100
        Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 05:41 +0100
          Re: How can I get the type in a C++17 fold function? scott@slp53.sl.home (Scott Lurndal) - 2022-12-16 15:17 +0000
            Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 18:22 +0100
              Re: How can I get the type in a C++17 fold function? scott@slp53.sl.home (Scott Lurndal) - 2022-12-16 17:42 +0000
                Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 19:20 +0100
            Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-28 16:41 -0800
              Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-29 03:40 +0100
                Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-28 22:27 -0800
              Re: How can I get the type in a C++17 fold function? Paavo Helde <eesnimi@osa.pri.ee> - 2022-12-29 09:36 +0200
                Re: How can I get the type in a C++17 fold function? Mason <mason.nobody@gmail.com> - 2022-12-29 17:15 +0000
                  Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-29 19:11 +0100
                Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-29 19:58 -0800
                  Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-30 08:09 +0100
                Re: How can I get the type in a C++17 fold function? Michael S <already5chosen@yahoo.com> - 2022-12-30 03:27 -0800
                  Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-30 14:01 +0100
                    Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-30 15:17 +0000
                      Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-30 20:04 +0100
                        Re: How can I get the type in a C++17 fold function? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-30 13:54 -0800
                        Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-31 15:33 +0000
                    Re: How can I get the type in a C++17 fold function? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2022-12-30 17:31 +0000
                      Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-01-02 13:30 -0800
                    Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-30 18:36 +0100

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#88284

scott@slp53.sl.home (Scott Lurndal) writes:

>    "While complexity seeks order through addition, simplicity
>     seeks it through subtraction.  Most people have a built-in bias
>     toward addition instead of subtraction.  For some reason, the
>     concept of more comes naturally to us."

It appears the original source of this quote is here:

    https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f

I encourage people to read the article.  Not that I think what it
says is deep or profound, I don't, but I think people might be
interested to read it.

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#88285

Am 29.12.2022 um 01:41 schrieb Tim Rentsch:

> It appears the original source of this quote is here:
> 
>      https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f
> 
> I encourage people to read the article.  Not that I think what
> it says is deep or profound, I don't, but I think people might
> be interested to read it.

And how does this make my example simpler ?

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#88290

Bonita Montero <Bonita.Montero@gmail.com> writes:

> Am 29.12.2022 um 01:41 schrieb Tim Rentsch:
>
>> It appears the original source of this quote is here:
>>
>>      https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f
>>
>> I encourage people to read the article.  Not that I think what
>> it says is deep or profound, I don't, but I think people might
>> be interested to read it.
>
> And how does this make my example simpler ?

I quoted all the text that was relevant to what I was saying.
You may notice that your name and your example did not appear in
the quoted text in any way.

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#88291

29.12.2022 02:41 Tim Rentsch kirjutas:
> scott@slp53.sl.home (Scott Lurndal) writes:
> 
>>     "While complexity seeks order through addition, simplicity
>>      seeks it through subtraction.  Most people have a built-in bias
>>      toward addition instead of subtraction.  For some reason, the
>>      concept of more comes naturally to us."
> 
> It appears the original source of this quote is here:
> 
>      https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f
> 
> I encourage people to read the article.  Not that I think what it
> says is deep or profound, I don't, but I think people might be
> interested to read it.

I guess that's how we arrive to "simple" user interfaces like unclear 
amount of white borderless text boxes on white background, some of which 
are maybe editable and some of which are maybe empty.

And then there are these phone apps which require unknown amount of hand 
gestures of unknown types, in unknown place, for interaction. But the 
interface looks simple.

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#88292

On 29/12/2022 07:36, Paavo Helde wrote:
>
>
>
> And then there are these phone apps which require unknown amount of 
> hand gestures of unknown types, in unknown place, for interaction. But 
> the interface looks simple.

We are going back to the good old days of "hieroglyphics". The 
Egyptians would be proud of us copying them.

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#88293

On 29 Dec 2022 18:15, Mason wrote:
> On 29/12/2022 07:36, Paavo Helde wrote:
>>
>>
>>
>> And then there are these phone apps which require unknown amount of
>> hand gestures of unknown types, in unknown place, for interaction. But
>> the interface looks simple.
> 
> We are going back to the good old days of "hieroglyphics". The
> Egyptians would be proud of us copying them.

It's a bit off topic this. But:

one main reason things get even more unusable by the quarter-year, is 
that the designers are conflating "simple to use" with "looks simple".

They are intellectually unable to grok "simple to use", because they are 
primarily selected for their ability to follow and to some degree be in 
the forefront of trends of popularity, secondly for their ability to put 
down hard repetitious work and work long hours, and third for their 
ability to sometimes be slightly creative as long as it is within 
established popular trends; they're not selected for intelligence and 
critical thinking, which runs counter to the three main criteria, i.e. 
would effectively be a disability for them.

Ultimately this depends on the consumers lacking a sense of quality and 
rewarding conformity and whatever is noticeable without a thought, like 
simple eye candy.

And they do.

Regarding "without a thought", an example a few months ago from the 
local grocery store: in the meat disk one slot was full of steaks, none 
sold, with price shown per kg., high, and the adjacent slot was nearly 
empty, with just a few steaks left, with price shown per steak, a much 
LOWER NUMBER  --  it was a best-seller, but it was the exact same price 
and the exact same product as the steaks that didn't sell.



- Alf

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#88302

Paavo Helde <eesnimi@osa.pri.ee> writes:

> 29.12.2022 02:41 Tim Rentsch kirjutas:
>
>> scott@slp53.sl.home (Scott Lurndal) writes:
>>
>>>     "While complexity seeks order through addition, simplicity
>>>      seeks it through subtraction.  Most people have a built-in bias
>>>      toward addition instead of subtraction.  For some reason, the
>>>      concept of more comes naturally to us."
>>
>> It appears the original source of this quote is here:
>>
>>      https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f
>>
>> I encourage people to read the article.  Not that I think what it
>> says is deep or profound, I don't, but I think people might be
>> interested to read it.
>
> I guess that's how we arrive to "simple" user interfaces like unclear
> amount of white borderless text boxes on white background, some of
> which are maybe editable and some of which are maybe empty.
>
> And then there are these phone apps which require unknown amount of
> hand gestures of unknown types, in unknown place, for interaction.  But
> the interface looks simple.

Yes, this is very much like my own reaction.

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#88305

Am 30.12.2022 um 04:58 schrieb Tim Rentsch:
> Paavo Helde <eesnimi@osa.pri.ee> writes:
> 
>> 29.12.2022 02:41 Tim Rentsch kirjutas:
>>
>>> scott@slp53.sl.home (Scott Lurndal) writes:
>>>
>>>>      "While complexity seeks order through addition, simplicity
>>>>       seeks it through subtraction.  Most people have a built-in bias
>>>>       toward addition instead of subtraction.  For some reason, the
>>>>       concept of more comes naturally to us."
>>>
>>> It appears the original source of this quote is here:
>>>
>>>       https://uxdesign.cc/the-quest-for-simplicity-5c31ae2c553f
>>>
>>> I encourage people to read the article.  Not that I think what it
>>> says is deep or profound, I don't, but I think people might be
>>> interested to read it.
>>
>> I guess that's how we arrive to "simple" user interfaces like unclear
>> amount of white borderless text boxes on white background, some of
>> which are maybe editable and some of which are maybe empty.
>>
>> And then there are these phone apps which require unknown amount of
>> hand gestures of unknown types, in unknown place, for interaction.  But
>> the interface looks simple.
> 
> Yes, this is very much like my own reaction.

Show me how to make that what I did with a simpler approach.
What I did isn't complex but just uncommon.

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#88306

On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
> 
> And then there are these phone apps which require unknown amount of hand 
> gestures of unknown types, in unknown place, for interaction. But the 
> interface looks simple.

And somehow kids manage to cope. Isn't it a little wonder?

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#88307

On 30 Dec 2022 12:27, Michael S wrote:
> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>
>> And then there are these phone apps which require unknown amount of hand
>> gestures of unknown types, in unknown place, for interaction. But the
>> interface looks simple.
> 
> And somehow kids manage to cope. Isn't it a little wonder?

Kids try out things and are great at memorizing arbitrary stuff. They're 
necessarily also vastly more smart than adults, in the sense of more 
flexible thinking and self-adjustment, though without the knowledge base 
that lets those smarts manifest as recognizable or measurable adult 
level intelligence. So when the UI changes (new phone, update, whatever) 
they just try out things and memorize the new ways, plus they 
communicate about such things so they can learn from other kids.

Adults rely more on a fixed established knowledge base, and the ability 
to apply a once learned set of rules to figure out how to do things, and 
many adults are prevented socially (I'll look dumb if I ask! I'm afraid 
of being put down!) from communicating much about such things.

An adult will explore but systematically, in accordance with the once 
learned rules, where kids will explore more at random. An adult has 
expectations, and can have "WTF?" reactions and back off, where a kid 
just happily accepts whatever happens and doesn't limit itself to what 
an adult may think is sensible.


- Alf

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#88308

On Fri, 30 Dec 2022 14:01:56 +0100
"Alf P. Steinbach" <alf.p.steinbach@gmail.com> wrote:
>On 30 Dec 2022 12:27, Michael S wrote:
>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>
>>> And then there are these phone apps which require unknown amount of hand
>>> gestures of unknown types, in unknown place, for interaction. But the
>>> interface looks simple.
>> 
>> And somehow kids manage to cope. Isn't it a little wonder?
>
>Kids try out things and are great at memorizing arbitrary stuff. They're 
>necessarily also vastly more smart than adults, in the sense of more 

Anyone who has kids knows thats not true. They're good at muscle memory 
learning. Not always academic learning.

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#88311

On 30 Dec 2022 16:17, Muttley@dastardlyhq.com wrote:
> On Fri, 30 Dec 2022 14:01:56 +0100
> "Alf P. Steinbach" <alf.p.steinbach@gmail.com> wrote:
>> On 30 Dec 2022 12:27, Michael S wrote:
>>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>>
>>>> And then there are these phone apps which require unknown amount of hand
>>>> gestures of unknown types, in unknown place, for interaction. But the
>>>> interface looks simple.
>>>
>>> And somehow kids manage to cope. Isn't it a little wonder?
>>
>> Kids try out things and are great at memorizing arbitrary stuff. They're
>> necessarily also vastly more smart than adults, in the sense of more
> 
> Anyone who has kids knows thats not true. They're good at muscle memory
> learning. Not always academic learning.
> 

Oh, they're good at anything, because mother Nature has designed them 
for precisely that: to learn an extreme amount of things in a short 
time, and to be able to survive without an adult's knowledge base. Brain 
plasticity is maximal as a newborn. At some point the loss of plasticity 
becomes critical also to ordinary thinking, so that e.g. mathematicians 
don't in general produce anything noteworthy after age 35 or so.


- Alf

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#88314

On 12/30/2022 11:04 AM, Alf P. Steinbach wrote:
> On 30 Dec 2022 16:17, Muttley@dastardlyhq.com wrote:
>> On Fri, 30 Dec 2022 14:01:56 +0100
>> "Alf P. Steinbach" <alf.p.steinbach@gmail.com> wrote:
>>> On 30 Dec 2022 12:27, Michael S wrote:
>>>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>>>
>>>>> And then there are these phone apps which require unknown amount of 
>>>>> hand
>>>>> gestures of unknown types, in unknown place, for interaction. But the
>>>>> interface looks simple.
>>>>
>>>> And somehow kids manage to cope. Isn't it a little wonder?
>>>
>>> Kids try out things and are great at memorizing arbitrary stuff. They're
>>> necessarily also vastly more smart than adults, in the sense of more
>>
>> Anyone who has kids knows thats not true. They're good at muscle memory
>> learning. Not always academic learning.
>>
> 
> Oh, they're good at anything, because mother Nature has designed them 
> for precisely that: to learn an extreme amount of things in a short 
> time, and to be able to survive without an adult's knowledge base. Brain 
> plasticity is maximal as a newborn. At some point the loss of plasticity 
> becomes critical also to ordinary thinking, so that e.g. mathematicians 
> don't in general produce anything noteworthy after age 35 or so.

Oh shit. I am 45!

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#88318

On Fri, 30 Dec 2022 20:04:58 +0100
"Alf P. Steinbach" <alf.p.steinbach@gmail.com> wrote:
>On 30 Dec 2022 16:17, Muttley@dastardlyhq.com wrote:
>> On Fri, 30 Dec 2022 14:01:56 +0100
>> "Alf P. Steinbach" <alf.p.steinbach@gmail.com> wrote:
>>> On 30 Dec 2022 12:27, Michael S wrote:
>>>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>>>
>>>>> And then there are these phone apps which require unknown amount of hand
>>>>> gestures of unknown types, in unknown place, for interaction. But the
>>>>> interface looks simple.
>>>>
>>>> And somehow kids manage to cope. Isn't it a little wonder?
>>>
>>> Kids try out things and are great at memorizing arbitrary stuff. They're
>>> necessarily also vastly more smart than adults, in the sense of more
>> 
>> Anyone who has kids knows thats not true. They're good at muscle memory
>> learning. Not always academic learning.
>> 
>
>Oh, they're good at anything, because mother Nature has designed them 
>for precisely that: to learn an extreme amount of things in a short 
>time, and to be able to survive without an adult's knowledge base. Brain 

Knowing a lot of things is not the same as being smart - ie being able to
problem solve novel situations and grasping complex abstract scenarios. 
Something many people, perhaps even the majority, don't seem to get as many
think someone who can parrot a load of Shakespeare or Descartes is some kind of
genius. 

>plasticity is maximal as a newborn. At some point the loss of plasticity 
>becomes critical also to ordinary thinking, so that e.g. mathematicians 
>don't in general produce anything noteworthy after age 35 or so.

True, ditto musicians and artists. Perhaps programmers too but a lot of good
stuff has been produced by middle aged guys.

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#88309

On Fri, 2022-12-30, Alf P. Steinbach wrote:
> On 30 Dec 2022 12:27, Michael S wrote:
>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>
>>> And then there are these phone apps which require unknown amount of hand
>>> gestures of unknown types, in unknown place, for interaction. But the
>>> interface looks simple.
>> 
>> And somehow kids manage to cope. Isn't it a little wonder?
>
> Kids try out things and are great at memorizing arbitrary stuff. They're 
> necessarily also vastly more smart than adults, in the sense of more 
> flexible thinking and self-adjustment, though without the knowledge base 
> that lets those smarts manifest as recognizable or measurable adult 
> level intelligence. So when the UI changes (new phone, update, whatever) 
> they just try out things and memorize the new ways, plus they 
> communicate about such things so they can learn from other kids.
>
> Adults rely more on a fixed established knowledge base, and the ability 
> to apply a once learned set of rules to figure out how to do things, and 
> many adults are prevented socially (I'll look dumb if I ask! I'm afraid 
> of being put down!) from communicating much about such things.

And grumpy old programmers are more likely to

- want to know what's really going on
- want to know the extent of the feature set behind
  the interface[1]
- know that the device may be their enemy
- have a distaste for magical thinking
- etc

> An adult will explore but systematically, in accordance with the once 
> learned rules, where kids will explore more at random. An adult has 
> expectations, and can have "WTF?" reactions and back off, where a kid 
> just happily accepts whatever happens and doesn't limit itself to what 
> an adult may think is sensible.

/Jorgen

[1] Personally I make an exception for Emacs. I have accepted that
    there are whole subcontinents of features I haven't mapped.

    As for C++ there's a lot I don't know, but I'm pretty sure I'm
    not missing out on anything major.

-- 
  // Jorgen Grahn <grahn@  Oo  o.   .     .
\X/     snipabacken.se>   O  o   .

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#88359

Jorgen Grahn <grahn+nntp@snipabacken.se> writes:

> On Fri, 2022-12-30, Alf P. Steinbach wrote:
>
>> On 30 Dec 2022 12:27, Michael S wrote:
>>
>>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>
>>>> And then there are these phone apps which require unknown amount
>>>> of hand gestures of unknown types, in unknown place, for
>>>> interaction.  But the interface looks simple.
>>>
>>> And somehow kids manage to cope.  Isn't it a little wonder?
>>
>> Kids try out things and are great at memorizing arbitrary stuff.
>> They're necessarily also vastly more smart than adults, in the
>> sense of more flexible thinking and self-adjustment, [...]

Kids are better at fast thinking.  Adults are better at slow
thinking.  Very few people are good at both.

> And grumpy old programmers are more likely to
>
> - want to know what's really going on
> - want to know the extent of the feature set behind
>   the interface[1]
> - know that the device may be their enemy
> - have a distaste for magical thinking
> - etc

I would say experienced programmers, whether or not they are
grumpy.

> [1] Personally I make an exception for Emacs.  I have accepted
>     that there are whole subcontinents of features I haven't
>     mapped.

I would be surprised to hear of any person who had mapped the
entire emacs command set.  Certainly I am not anywhere close to
knowing the extent of emacs geography, and I've been a regular
emacs user for more than 40 years.

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#88310

Am 30.12.2022 um 14:01 schrieb Alf P. Steinbach:
> On 30 Dec 2022 12:27, Michael S wrote:
>> On Thursday, December 29, 2022 at 9:36:17 AM UTC+2, Paavo Helde wrote:
>>>
>>> And then there are these phone apps which require unknown amount of hand
>>> gestures of unknown types, in unknown place, for interaction. But the
>>> interface looks simple.
>>
>> And somehow kids manage to cope. Isn't it a little wonder?
> 
> Kids try out things and are great at memorizing arbitrary stuff. They're 
> necessarily also vastly more smart than adults, in the sense of more 
> flexible thinking and self-adjustment, though without the knowledge base 
> that lets those smarts manifest as recognizable or measurable adult 
> level intelligence. So when the UI changes (new phone, update, whatever) 
> they just try out things and memorize the new ways, plus they 
> communicate about such things so they can learn from other kids.
> 
> Adults rely more on a fixed established knowledge base, and the ability 
> to apply a once learned set of rules to figure out how to do things, and 
> many adults are prevented socially (I'll look dumb if I ask! I'm afraid 
> of being put down!) from communicating much about such things.
> 
> An adult will explore but systematically, in accordance with the once 
> learned rules, where kids will explore more at random. An adult has 
> expectations, and can have "WTF?" reactions and back off, where a kid 
> just happily accepts whatever happens and doesn't limit itself to what 
> an adult may think is sensible.

That's not a matter of reasoning.
Kids are just more open-minded than you.

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