Perform a lexicographic three-way comparison of the specified lhs and the specified rhs maps by using the comparison operators of bsl::pair<const KEY, VALUE> on each element; return the result of that comparison.
Declared in <bslstl_map.h>
template<
class KEY,
class VALUE,
class COMPARATOR,
class ALLOCATOR>
BloombergLP::bslalg::SynthThreeWayUtil::Result<bsl::pair<KEY const, VALUE>>
operator<=>(
map<KEY, VALUE, COMPARATOR, ALLOCATOR> const& lhs,
map<KEY, VALUE, COMPARATOR, ALLOCATOR> const& rhs);