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
The easiest approach would be first to write a composition of 2 functions: def compose2(f, g): return lambda *a, **kw: f(g(*a, **kw)) And then use reduce to compose more functions: import functools def compose(*fs): return functools.reduce(compose2, fs) Or you can use some library, which already contains compose function.
Self type annotations allow you to express cyclic dependencies. For instance: trait A extends B trait B { self: A => } This is not possible with simple inheritance.
Please note that there are different interpretations of the “association” definitions. My views below are heavily based on what you would read in Oracle Certification books and study guides. Temporary association A usage inside a method, its signature or as a return value. It’s not really a reference to a specific object. Example: I park … Read more
Foo f1; Foo f2(f1); Yes this will do what you expect it to: The f2 copy constructor Foo::Foo(Foo const&) is called. This copy constructs its base class and then each member (recursively) If you define a class like this: class X: public Y { private: int m_a; char* m_b; Z m_c; }; The following methods … Read more
The language is irrelevant when dealing with composition vs inheritance. If you understand what class is and what an instance of a class is, then you have all you need. Composition is simply when a class is composed of other classes; or to say it another way, an instance of an object has references to … Read more
Delegation public class A { private B b = new B(); public void methodA() { b.methodB(); } } When clients of A call methodA, class A delegates the call to B‘s methodB. Rationale. Class A exposes behaviours that belong elsewhere. This can happen in single-inheritance languages where class A inherits from one class, but its … Read more
[note: This question was originally tagged as being language-agnostic. Based on that, this answer was written to be fairly language agnostic, so it discusses inheritance as it’s used across a wide range of languages, such as Smalltalk, C++, and Object Pascal. It’s since been re-tagged as being specifically about Java. Java is different in defining … 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
This is easy once you realize that Object-Oriented Constructor Injection corresponds very closely to Functional Partial Function Application. First, I’d write Dings as a record type: type Dings = { Lol : string; Rofl : string } In F#, the IGetStuff interface can be reduced to a single function with the signature Guid -> seq<Dings> … Read more