It is definitely not good to inherint Child from Parent or Parent from Child. The correct way to do it is to make a base class, let’s say Person and inherit both Child and Parent from it. An advantage of doing this is to remove code repetition, at the moment you have only firstname / … Read more
Mark, This is an interesting question. You will find as many opinions on this. I don’t believe there is a ‘right’ answer. This is a great example of where a rigid heirarchial object design can really cause problems after a system is built. For example, lets say you went with the “Customer” and “Staff” classes. … Read more
Note: These features (blur and the Backdrop brush) require the Anniversary Update to Windows 10. You currently can get a preview of the SDK through the Windows Insider Program Prerequisites Targeting the Windows 10 Anniversary Update A basic understanding of the Visual Layer and how the Visual Tree works. You can find out more here. … Read more
Scott Meyers in “Effective C++” item 42 says “Only inheritance gives access to protected members, and only inheritance allows for virtual functions to be redefined. Because virtual functions and protected members exist, private inheritance is sometimes the only practical way to express an is-implemented-in-terms-of relationship between classes.”
Basic technologies (such as XML, SOAP, WSDL) provide means to describe, locate, and invoke services as an entity in its own right. However, these technologies do not give a rich behavioral detail about the role of the service in more complex collaboration. This collaboration includes a sequence of activities and relationships between activities, which build … Read more
Composition refers to combining simple types to make more complex ones. In your example, composition could be: Animal: Skin animalSkin Organs animalOrgans Mammal::Animal: Hair/fur mammalFur warm-blooded-based_cirulation_system heartAndStuff Person::Mammal: string firstName string lastName If you wanted to go totally composition (and get rid of all inheritance) it would look like this: Animal: Skin animalSkin Organs animalOrgans … Read more
Consider this monad which is isomorphic to the (Bool ->) monad: data Pair a = P a a instance Functor Pair where fmap f (P x y) = P (f x) (f y) instance Monad Pair where return x = P x x P a b >>= f = P x y where P x … Read more
The question as it stands is a bit unclear IMO. To give a more general answer that you can apply to a scenario where you need clipping you can use (at least) two approaches: Method 1 – Using composite mode to clip Composite mode is the simplest way but also the least flexible as you … Read more
Actually, doing arbitrary arity with type classes turns out to be incredibly easy: module Pred where class Predicate a where complement :: a -> a instance Predicate Bool where complement = not instance (Predicate b) => Predicate (a -> b) where complement f = \a -> complement (f a) — if you want to be … Read more
Note that this is to be done differently in JSF 2.x Facelets, see this answer for detail. This is possible with a custom Facelets resource resolver. I would only not resolve them by HTTP, but just from the classpath. Just package the shared templates in for example the /META-INF/resources folder of the JAR file and … Read more