Same as the primary operator+ with a C-string lhs and rvalue rhs.
Declared in <bslstl_string.h>
template<
class CHAR_TYPE,
class CHAR_TRAITS,
class ALLOCATOR>
bsl::basic_string<CHAR_TYPE, CHAR_TRAITS, ALLOCATOR>
operator+(
CHAR_TYPE const* lhs,
bsl::basic_string<CHAR_TYPE, CHAR_TRAITS, ALLOCATOR>&& rhs);