super

I'm learning react from the docs , but not sure what the super() does in this example. Usually, doesn't it take the arguments that are passed to making a new instance and then calls React.Component's constructor method to incorporate these arguments into the instance? What does it do without any arguments? class LikeButton extends React.Component { constructor() { super(); this.state = { liked: false }; this.handleClick = this.handleClick.bind(this); } handleClick() { this.setState({liked: !this.state.liked}); } render() { const text = this.state.liked ? 'liked' : 'haven\'t liked'; return (

Let's say I have the following classes set up: class Foo: def __init__(self, frob, frotz): self.frobnicate = frob self.frotz = frotz class Bar: def __init__(self, frob, frizzle): self.frobnicate = frob self.frotz = 34 self.frazzle = frizzle How can I (if I can at all) use super() in this context to eliminate the duplicate code? JAB In Python >=3.0, like this: class Foo(): def __init__(self, frob, frotz) self.frobnicate = frob self.frotz = frotz class Bar(Foo): def __init__(self, frob, frizzle) super().__init__(frob, 34) self.frazzle = frizzle Read more here: http://docs.python.org/3.1/library

I'm trying to learn the super() function in Python. I thought I had a grasp of it until I came over this example (2.6) and found myself stuck. http://www.cafepy.com/article/python_attributes_and_methods/python_attributes_and_methods.html#super-with-classmethod-example Traceback (most recent call last): File "<stdin>", line 1, in <module> File "test.py", line 9, in do_something do_something = classmethod(do_something) TypeError: unbound method do_something() must be called with B instance as first argument (got nothing instead) >>> It wasn't what I expected when I read this line right before

I'm just diving into some more advanced python subjects (well, advanced to me at least). I am now reading about multiple inheritance and how you can use super(). I more or less understand the way the super function is used, but (1) What's wrong with just doing it like this ?: class First(object): def __init__(self): print "first" class Second(object): def __init__(self): print "second" class Third(First, Second): def __init__(self): First.__init__(self) Second.__init__(self) print "that's it" On to super(), Andrew Kuchlings paper on Python Warts says: usage of super() will also be correct when

I'm new to python, I have the code below which I just can't get to work:- This is inheritance, I have a circle base class and I inherit this within a circle class (just single inheritance here). I understand the issue is within the ToString() function within the circle class, specifically the line, text = super(Point, self).ToString() +.. which requires at least a single argument, yet I get this: AttributeError: 'super' object has no attribute 'ToString' I know super has no ToString attribute, but the Point class does - My code: class Point(object): x = 0.0 y = 0.0 # point class constructor

! Hola, amigos. I have this little class inheritance structure class Point { constructor(x, y) { this.x = x; this.y = y; } toString() { return '(' + this.x + ', ' + this.y + ')'; } } class ColorPoint extends Point { constructor(x, y, color) { super(x, y); this.color = color; } toString() { return super.toString() + ' in ' + this.color; } } let newObj = new ColorPoint(25, 8, 'green'); It compiles to this jsfiddle I get how it works in es6 in a silly way. But could somebody explain how does it work under the hood in es5. In a simpler form. Bergi super(…); is basically sugar for this = new

I have an init method that is used and overridden through out an extensive heirarchy. Each init call however extends on the work that the previous did. So naturally, I would: @Override public void init() { super.init(); } And naturally this would ensure that everything is called and instantiated. What I'm wondering is: Can I create a way to ensure that the super method was called? If all of the init's are not call, there is a break down in the obejct, so I want to throw an exception or an error if somebody forgets to call super . TYFT ~Aedon Here's one way to raise an exception if a derived