C++11: The range-based for statement: “range-init” lifetime?

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Is this reasoning correct? If not, why not?

It is correct up until this point:

And so the temporary return value of boo() is destroyed at the end of the statement “auto&&r=boo()” […]

Binding a temporary to a reference extends its lifetime to be that of the reference. So the temporary lasts for the whole loop (that’s also why there is an extra set of {} around the whole construct: to correctly limit the lifetime of that temporary).

This is according to paragraph 5 of ยง12.2 of the C++ standard:

The second context is when a reference is bound to a temporary. The
temporary to which the reference is bound or the temporary that is the
complete object of a subobject to which the reference is bound
persists for the lifetime of the reference except:

[various exceptions that don’t apply here]

This is an interesting property that allows abusing the ranged-for loop for non-rangey things: http://ideone.com/QAXNf

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