How many constructors does the class have?

There is only one constructor corresponding to the posted declaration, not three overloads. The calls Fraction(); Fraction(n); are equivalent to: Fraction(0, 1); Fraction(n, 1); One more way to convince yourself that there is only one constructor corresponding to the declaration is that you only need to define one constructor, not three. The section of the …

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How to overload constructor of an Object in JS (Javascript)?

You can’t do that, since JavaScript is not a strongly typed language it will not see a difference between form and userName. You can create multiple function like createUserFromForm(form) and createUserFromUserInfo(userName, password,…) or you could try to use a singular constructor with no arguments specified and then use arguments collection to check the input and …

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How does Python’s “super” do the right thing?

Change your code to this and I think it’ll explain things (presumably super is looking at where, say, B is in the __mro__?): class A(object): def __init__(self): print “A init” print self.__class__.__mro__ class B(A): def __init__(self): print “B init” print self.__class__.__mro__ super(B, self).__init__() class C(A): def __init__(self): print “C init” print self.__class__.__mro__ super(C, self).__init__() class …

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Creating a Fragment: constructor vs newInstance()

I personally find that using constructors is a much more common practice than knowing to use newInstance() and passing parameters. The factory method pattern is used fairly frequently in modern software development. So basically my question is, why does Google not want you to use constructors with parameters for Fragments? You answered your own question: …

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JavaScript: The Good Parts – How to not use `new` at all

Crockford gives an example for an object creation function as should have been provided by JS itself in one of his Javascript talks available on http://developer.yahoo.com/yui/theater/ However, the YUI(3) team itself uses “new”, and they DO follow his recommendations (since he’s the Yahoo chief JS architect (UPDATE: he moved on, but the statement was true …

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Javascript: Mocking Constructor using Sinon

I needed a solution for this because my code was calling the new operator. I wanted to mock the object that the new call created. var MockExample = sinon.stub(); MockExample.prototype.test = sinon.stub().returns(“42”); var example = new MockExample(); console.log(“example: ” + example.test()); // outputs 42 Then I used rewire to inject it into the code that …

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