One of the comment in C++11 for rvalue references is incorrect about modern-cpp-features HOT 5 CLOSED

Hi @AnthonyCalandra ,

Thank you for clarifying. My interpretation of your statement was incorrect, I thought you are referring xr2 as lvalue reference but after reading carefully, I understood.

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Hi @gulipalli123 , this is a common misconception; the comment is actually correct as xr2 is itself an lvalue, with type int&&. See the following post which describes this in detail: http://thbecker.net/articles/rvalue_references/section_05.html

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Hi Anthony,

From Item24: Distinguish universal references from rvalue references of "Effective Modern C++" , it is clear that it is a rvalue references. Also I have tried compiling with an example, the results are as in the attachment.

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Kindly let me know if there is some misunderstanding from myside.

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Hi @gulipalli123 ,

xr2 is absolutely an rvalue reference -- there's no doubt about it, I agree. :) However, because the rvalue reference has a name (the name of the variable is xr2), it will behave as an lvalue, which is what the comment tries to make clear. There is a distinction between what the value category the reference binds to, and what the variable's value category is itself.

To help show you the above explanation in a code example, I have a small one here I want you to try running: https://godbolt.org/z/TvWYvP3aY
Notice there are no universal references here, just an lvalue reference and an rvalue reference. What does it print and why?

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