I found this code on a web site #include <iostream> using namespace std; struct Base { Base() { cout << \"Base\" << \" \"; }
Can I write a class which 开发者_如何学Pythonhas virtual methods - (which can be overridden but have a default behaviour) and also abstract methods - (which have to be overridden)
In (very) modern GHC\'s, I can write this: {-# LANGUAGE TypeFamilies #-} -- consider this part \"library\" code, changeable at will
In the comments of this answer it is stated that \"checking whether the object has implemented the interface , rampant as it may be, is a bad thing\"
I have a table User that inherits from a table called Person Long story short, instead of having to do the following:
This qu开发者_Python百科estion already has answers here: Closed 11 years ago. Possible Duplicate: Try to describe polymorphism as easy as you can
I\'ve got this model class Question < ActiveRecord::Base has_many :votes def to_s \"hello?\" end end and when I attempt to display a Question with <%= @qu开发者_如何学Pythonestion %>
Is it possible to write an injective function of type hard :: (forall n . Maybe (f n)) -> Maybe (forall n . (f n))
A friend and I are studying Java. We were looking at interfaces today and we got into a bit of an discussion about how interfaces are used.
I have a base class that has a subclass (could be a struct i suppose but not sure if it\'s appropriate) and a method.
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