Is it ok to do namespace ranges = std::ranges;

Question

Since C++20, it seems that std::ranges:: is capable of almost everything std:: can do (looking at range algorithms).

Is it a good practice to just write namespace ranges = std::ranges; in the topmost header of one's project ?

For example, a namespace alias is already done for views:

namespace std {
    namespace views = ranges::views;
}

EDIT @StoryTeller - Unslander Monica: one single question

Please only ask one question per-question. #3 is answered [here](https://stackoverflow.com/q/64518019/817643). #2 is because **all** the C++ standard library is in namespace std. The only exceptions are C legacy and macros. — StoryTeller - Unslander Monica, Feb 17 '21 at 09:10

score 1 · Accepted Answer · answered Feb 17 '21 at 11:34

We don't want to pollute the global space with a second namespace.

When developing a library, you can do this inside your MyLib namespace so that there is no pollution => it is convenient because you can simply use ranges:: inside the MyLib scope, whatever the header or the source file.
When developing a simple project, you can do this in a "define.hpp" file because it is up to you to decide what ranges:: means (the standard protects your right to alias it or not following if you already have a ranges class for example).

So yes, it is OK as long as you don't pollute one's people global scope with your API.

1 Answers1