Почему я не могу создать цепочку после std::ranges::views::join? ⇐ C++

[Гость]

I recently discovered the ranges stdandard library and encountered a strange behavior. When chaining multiple range adaptors, I can't chain after using

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std::ranges::views::join

:

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vec | std::ranges::views::slide(2) | std::ranges::views::join

works as intended, but

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vec | std::ranges::views::slide(2) | std::ranges::views::join | std::ranges::views::slide(2)

will result in compilation error:

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error: no match for 'operator|' (operand types are 'std::ranges::join_view' and 'std::ranges::views::__adaptor::_Partial')
265 |   vec | std::ranges::views::slide(2) | std::ranges::views::join | std::ranges::views::slide(2);
|   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|                                      |                                                     |
|                                      |                                                     std::ranges::views::__adaptor::_Partial
|                                      std::ranges::join_view

Why is that? and what do I have to do to make multiple joins work?
Thanks in advance!


Источник: https://stackoverflow.com/questions/781 ... sviewsjoin