std::experimental::optional operator!=

--- Begin Message --- Hi, When trying to convert some code using boost::optional to using std::experimental::optional instead if come over the issue that I had to implement operator!= for the contained types. When looking at n3793 it states that operator!= should be implemented with !(t1 == t2),

[PATCH] std::quoted is too eager to clear the string

* include/std/iomanip (_Quoted_string operator>>): Do not clear string if input is not quoted. Currently the string is cleared regardless of how the string is handled. This patch just moves the clearing down so that we do not clear it if we are not going to quote the string (i.e. let operator