On Tue, May 2, 2023 at 10:10 AM Victor Eijkhout via SG20 <sg20@lists.isocpp.org> wrote:
>
> Unfortunately, I'm not in a position to try out this approach on real
> students. My experience is that namespaces are seen as mysterious and
> scary, but I don't know if that would be so if they were used in simple
> ways from day #1.

On day 1 they are learning what a loop is. Day 2 a function, day 3 objects, day 4 containers. Maybe on day 10 they write something that is even big enough for separate compilation. (Which brings up the question of headers, makefiles, build systems. Day 11?)

Point being there are many things that I would like to do on day 1, but my students brain capacity is limited. Last semester I tried integrating unit testing in a beginners course. With mixed success. Namespaces? Unless I can come up with a convincing enough example why they need it I’m not teaching it.

Whereas I would say that CS students, at least, should be familiar with the idea of hierarchical names through
- Web domain names (books.google.com is the `books` member of google.com, which is the `google` member of com)
- Directory/subfolder structures (/~ajo/bin is the `bin` subdirectory of `/~ajo`, which is the `~ajo` subdirectory of root)
- Chapter subheadings in books (section 1.1 is the first subsection of Chapter 1)
- If they already know some programming, then: objects and structs (car.wheels is the `wheels` member of the car)

With that attitude, a hierarchical (qualified) name like "std::string" is simply the "string" that is a member of the "std" namespace. Its full name is "std::string", and that's how we're always going to refer to it in this course.  Things that come from the standard library are always qualified with "std"; if you see "std", then you know you can go look that thing up on cppreference (or just google it, in general).  Things that don't come from the standard library — things I just made up for this class — will never be prefixed by "std". If you have a question about something not in "std", you'll have to ask around here, because you'll know it's not part of the portable standard.

This matches what someone else said, about not teaching students to form wrong expectations regarding `std::vector`.  If I have to choose between a new hire confusedly asking:
(1) "Hey, I'm not really comfortable with this `std::vector` thing. My teacher always used `ppp::vector` instead. Do we have `ppp::vector` here?"
(2) "Hey, this code I wrote seems to be behaving wrong at runtime, with no message or anything, almost like it's... wrapping the index, or giving me back a dummy value, or something? Shouldn't it safely abort when the index is out of bounds? Does our `std::vector` have a bug or something?"
I would vastly prefer to deal with question #1 than with question #2.

 
PS does someone know how to properly reply to a msg in a digest?

I believe this is one of those cases where "if you have to ask, the answer is no."  I believe it's impossible through Gmail.  If you can control your email client's message headers, then I'm sure it's possible to do it the greybeard way — just go look up the `Message-ID` of the original post you want to respond to (e.g. in this case <606f4a64-b4a2-41a6-77a0-bd4d3223da55@stroustrup.com>, which is almost entirely visible if you look at the HTML comments inside https://lists.isocpp.org/sg20/2023/05/0352.php — I guess our hypothetical greybeard would also have to know Bjarne's email domain by heart), and paste that Message-ID into the `In-Reply-To` header of your reply. Ta-da, easy as pie. ;)

–Arthur