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Comment by noobermin | Hacker News Reader

God, C++ even today is still horribly verbose. I get that being "explicit" is being "better" but there are limits. Even after auto removed a lot of verbosity there still is a lot there just to get it to do exactly what you want.

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Here's how it looks when you write readable C++:

    for (const auto &[x, y]: zip(a, subrange(begin(b), unreachable_sentinel))) {
        /* Do something with x and y */
    }

I'm not sure why C++ programmers don't like using `using`, it's as if Java programmers insist on typing out java.util.ArrayList every time because you may have an ArrayList of your own in the future.

So much C++ code can become readable by adding `using namespace std::something`.

The reason is header files. If you do `using namespace std::something` in one file and it gets included in another, the other file now has std::something in the global namespace which it may not have excepted.

Other languages like Java have imports scoped a to a single file, so this is not a problem.

I see, but that's only a program in header files, isn't it? Most code will end up in .cpp files which don't get included (usually).

It makes sense to use std::vector in a .h(pp) file, but in the .cpp you should be able to `using namespace std`, right?

Most code will end up in .cpp files which don't get included (usually).

Not if a lot of your code is in the form of templates. You have to put those in headers.

At this point, just use a modern language already d=

Not when using modules.

The word "antiquated" comes to mind, but it's worse than that. An age-old self-created fractal hell of dumb problems created by a simplistic view of code reuse based on the simple mechanism of text inclusion that constantly restrains future evolution. It's antediluvian and just plain backwards.

We are at least getting modules real soon now: https://en.cppreference.com/w/cpp/language/modules

We've been getting them real soon for… about 5 years now?

They were supposed to be part of C++11, back when it was called C++0x, before getting punted. So more like almost 20 years now (since some time after C++03.)

Java is still trying to get value types.

Some things take time when trying to avoid Python 2 / 3 scenarios.

The Python 2/3 scenario was because of breaking backward compatibility, which is not the case for C++ modules.

The only compiler that seems to care about implementing modules is MSVC. It'll be "real soon" when GCC stops crashing.

I think there's a GCC branch that implements module, and it seemed pretty stable. But there must be a reason why it's not merged yet so you're most likely right.

Many are quite happy to only use VC++.

Using in a header file => complete no-no.

Using in a cpp file => absolutely fine.

> Using in a cpp file => absolutely fine.

definitely not as soon as you want to do unity/jumbo builds (which are in my experience the n°1 thing to do to get fast CI builds)

It should be completely fine to use `using namespace std` inside a function body right ?

C++ doesn't have a lot of namespacing below 'std', so if you go around using everything you need, you end up with a lot of short, possibly conflicting names in scope.

Java avoids this somewhat because functions are always in a class, so there is a little bit of extra namespacing, even if you've imported the class.

You can still import fully qualified static method on a class:

import someclass.doThing;

Or maybe that's what you meant by somewhat :)

Don’t the boost libraries use a bunch of namespacing? And I think you need boost to be decently useful in c++.

I see the same thing in PHP. Example code full of inline namespace-qualified paths and a lot of array() instead of [] as if nothing changed since PHP4.

In an actual .cpp compilation unit, I'd probably write it like that.

In a header it's generally advised to not add using namespaces.

However, I appreciate the grandparent comment including the namespaces in the example, so I can see exactly where things are coming from.

What is verbose about that? (The first case, not the second, special case)

Seems hard to make it any shorter. Well, I guess you could remove "const" if you want.

I don't do C++ but if it's anyting like my Java IDE most of that stuff pops up in autocomplete and you just tab through it all

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