A beginner's guide to C++ Ranges and Views.

[h-2]

See https://hannes.hauswedell.net/post/2019/11/30/range_intro/

[mull]

Great article!

I noticed a problem with the markdown inside the collapsing elements, particularly the last one named "Here is the solution". Just wanted to mention it if it had gone unnoticed so far :-)

[NBJack]

This is honestly the best guide I've found trying to understand Ranges and their relationship to Iterators. Great work.

I did notice a formatting issue in the code samples on my device: line numbers are appearing immediately to the left of the code. This makes it harder to read (though the change in color alleviates it).

.

[an146]

Is there function like std::ranges::uniq :: range -> optional? Motivation: http://movepoint.su/anekforhire/ https://gcc.godbolt.org/z/zv8hbW45n

[wxinix]

Thank you for the article. Would std::views have any performance implications?

[h-2]

Slowly catching up with the comments 😇

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@NBJack :

This is honestly the best guide I've found trying to understand Ranges and their relationship to Iterators. Great work.

Thank you very much!

I did notice a formatting issue in the code samples on my device: line numbers are appearing immediately to the left of the code.

Yeah, I had some trouble with the blog, because I wanted rendering to happen server-side and not via javascript. This is apparently quite difficult in the modern days ™️ . I plan to update the blog system sometime soon and then also improve the code snippets.

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@an146 :

Is there function like std::ranges::uniq :: range -> optional?

I am not sure what you want exactly. Are you looking for a view or are you looking for an algorithm that transforms a range into a single value (like a fold)?

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@wxinix :

Thank you for the article. Would std::views have any performance implications?

Some of them do, some don't. It depends on the view and also on the type of the underlying range. In my experience, std::views::transform on top of something like a vector or array has almost no impact. The same goes for "slicing" views (take and drop). I have measured a little overhead for filter-views, but this depends also on how predictable the predicate is that you are evaluating. I wrote more on this in my thesis: https://refubium.fu-berlin.de/bitstream/handle/fub188/30952/dissertation_hauswedell_refubium_version2.pdf?sequence=3&isAllowed=y (page 166 and following).

[h-2]

It took a while, but all formatting issues should be fixed (I hope).

[maksverver]

Very helpful post! I came here searching for the difference between C++ spans, ranges, and views, and this article explained it clearly and succinctly.

One complaint about styling though: in the table under “well-known containers from the standard library” the column headers are very hard to read. There is barely any contrast between the green background and light grey text colors.

[h-2]

Very helpful post! I came here searching for the difference between C++ spans, ranges, and views, and this article explained it clearly and succinctly.

Thank you!

One complaint about styling though: in the table under “well-known containers from the standard library” the column headers are very hard to read. There is barely any contrast between the green background and light grey text colors.

Fixed it!

[alexanderchuranov]

A very useful introduction to C++ ranges! Brief and to the point. Thank you!