Swift中实现可比较协议

public class EQ:NSObject
{

}

extension EQ: Comparable {}

public func ==(lhs: EQ,rhs: EQ) -> Bool
{
return true
}

public func <(lhs: EQ,rhs: EQ) -> Bool
{
return true
}

public func <=(lhs: EQ,rhs: EQ) -> Bool
{
return true
}

public func >=(lhs: EQ,rhs: EQ) -> Bool
{
return true
}

public func >(lhs: EQ,rhs: EQ) -> Bool
{
return true
}

用法：

let eq1 = EQ()

let eq2 = EQ()

print(eq1 > eq2)