On 13 February 2014 03:23, Florian Weimer wrote: > > I think the ""f operator has not been implemented in C++1y mode, either > because it's not actually part of the standard or no one has found the time > to implement it yet. f is not a user-defined literal operator, it's a core language feature present in C and C++, but not valid on integer-literals such as 42.