subclass

Subclassing a Python dict works as expected: >>> class DictSub(dict): ... def __init__(self): ... self[1] = 10 ... >>> DictSub() {1: 10} However, doing the same thing with a collections.OrderedDict does not work: >>> import collections >>> class OrdDictSub(collections.OrderedDict): ... def __init__(self): ... self[1] = 10 ... >>> OrdDictSub() (…) AttributeError: 'OrdDictSub' object has no attribute '_OrderedDict__root' Thus, the OrderedDict implementation uses a private __root atribute, which prevents the subclass OrdDictSub from behaving like the DictSub subclass. Why? How can one inherit

Customizing pprint.PrettyPrinter The documentation for the pprint module mentions that the method PrettyPrinter.format is intended to make it possible to customize formatting. I gather that it's possible to override this method in a subclass, but this doesn't seem to provide a way to have the base class methods apply line wrapping and indentation. Am I missing something here? Is there a better way to do this (e.g. another module)? Alternatives? I've checked out the pretty module, which looks interesting, but doesn't seem to provide a way to customize formatting of classes from other modules

My goal is to set the textColor of my custom UILabel subclass in my view controller. I have a UILabel subclass named CircleLabel . Here are the basics of it: class CircleLabel: UILabel { required init(coder aDecoder: NSCoder) { super.init(coder: aDecoder)! } override init(frame: CGRect) { super.init(frame: frame) } override func drawRect(rect: CGRect) { self.layer.cornerRadius = self.bounds.width/2 self.clipsToBounds = true super.drawRect(rect) } override func drawTextInRect(rect: CGRect) { self.textColor = UIColor.whiteColor() super.drawTextInRect(rect) } func setProperties(borderWidth: Float

I have the following class, with an init method: class user { var name:String var address:String init(nm: String, ad: String) { name = nm address = ad } } I'm trying to subclass this class but I keep getting errors on the super.init() part: class registeredUser : user { var numberPriorVisits: Int // This is where things start to go wrong - as soon as I type 'init' it // wants to autocomplete it for me with all of the superclass' arguments, // and I'm not sure if those should go in there or not: init(nm: String, ad: String) { // And here I get errors: super.init(nm: String, ad: String) // etc..

I would like to test whether a class inherits from another class, but there doesn't seem to exist a method for that. class A end class B < A end B.is_a? A => false B.superclass == A => true A trivial implementation of what I want would be: class Class def is_subclass_of?(clazz) return true if superclass == clazz return false if self == Object superclass.is_subclass_of?(clazz) end end but I would expect this to exist already. Marcel Jackwerth Just use the < operator B < A # => true A < A # => false or use the <= operator B <= A # => true A <= A # => true Also available: B.ancestors.include? A

So I have two classes: Property and Houses . Property is the abstract super class and Houses is its subclass. Here is the code for Property public abstract class Property{ String pCode; double value; int year; public Property(String pCode, double value , int year){ this.pCode = pCode; this.value = value; this.year = year; } public Property(){ pCode = ""; value = 0; year = 0; } public abstract void depreciation(); //Accessors private String getCode(){ return pCode; } private double getValue(){ return value; } private int getYear(){ return year; } //Mutators private void setCode(String newCode){

Why doesn't it work for the built-in classes? Is using a subclass the best approach to fix it, or will I run into some hidden problems? a = {} a.p = 1 # raises AttributeError class B(dict): pass b = B() b.p = 1 # works EDIT: my original comment that it doesn't work for b was incorrect (I made a mistake). The builtin classes do not have the ability to have arbitrary attributes. This is done for reasons of performance, especially memory usage, you want the built-in classes like list and dict to be as small as possible so you can have many of them. Therefore the built-in classes do not have the _

I have a strange issue, my subclassing works in all my view controllers except one. I have imported everything that is required, but this one class is giving me the "Missing argument for parameter 'className' in call" My subclass import Foundation import Parse class Session : PFObject, PFSubclassing { class func parseClassName() -> String { return "Session" } } // i have removed the non important info I perform the Session.registerSubclass() In the app delegate In EVERY class I have i can create a session via var se = Session() But in this one class, this will not work. The class import UIKit