deep-copy

问题 I understand the differences between shallow copy and deep copy as I have learnt in class. However the following doesn't make sense import copy a = [1, 2, 3, 4, 5] b = copy.deepcopy(a) print(a is b) print(a[0] is b[0]) ---------------------------- ~Output~ >False >True ---------------------------- Shouldn't print(a[0] is b[0]) evaluate to False as the objects and their constituent elements are being recreated at a different memory location in a deep copy? I was just testing this out as we had

问题 Although I know the main difference between Deep Copy and Shallow Copy but what I want to ask here is something practical. I have NSArray *firstArray = [NSArray arrayWithObjects:@"first", @"second",@"third", nil]; NSArray *secondArray = firstArray; secondArray = nil; NSLog(@"First Array : %@",firstArray); NSLog(@"Secon Array : %@",secondArray); Both the firstArray and secondArray has the same reference as seen by putting break point. Now my question is this, if both have same REFERENCE then

问题 I have two Generated Interfaces IPerson and IAddress . However I have defined Property Interfaces which Inherit from those base Interfaces Interfaces public interface IPerson_Name : IPerson { String Name{get;set;}} public interface IPerson_Addresses : IPerson { ICollection<IAddress> Addresses{ get; set; } IAddress NewAddress(); } public interface IAddress_Line1 : IAddress { String Line1 { get; set; } } Then I have two implementations of each of the base interfaces Implementation public class

问题 I currently have a three dimensional NSMutableArray which I need to deep copy. However, it appears that the following code causes it and its contents to become immutable, since it causes NSInvalidArgumentException when I attempt to remove any objects from it. NSMutableArray* copy = [[[NSMutableArray alloc] initWithArray:input copyItems:YES] autorelease]; How can I deep copy an array without causing it to become immutable? 回答1: From the listing, The copy imlementation of immutable classes

问题 I have a graph data structure Overlay , which consists of instances that are interconnected by edges. Instances are represented by a set of Instance -objects and edges are represented by a set of Edge -objects. For convenience, each instance keeps track of the in- and outgoing edges by pointing to the corresponding existing Edge -objects. Similarly, each edge points to the source- and the destination- Instance -object. For example, an overlay may consist of an instance i1 that is connected to

问题 Essentially what I want to do is copy a WebBrowser object such that I can do the equivalent of "Open In New Tab" or "Open In New Window" actions, maintaining any posted data. I don't just want to navigate to the same URL as in the original WebBrowser object, rather I want to repeat the HttpWebRequest. Is this possible? How? 回答1: I believe the WebBrowser object is a control, and therefore it has a window handle, which is going to cause issues if you try to clone it. I don't think you're going

问题 I would like to make a deepcopy of a function in Python. The copy module is not helpful, according to the documentation, which says: This module does not copy types like module, method, stack trace, stack frame, file, socket, window, array, or any similar types. It does “copy” functions and classes (shallow and deeply), by returning the original object unchanged; this is compatible with the way these are treated by the pickle module. My goal is to have two functions with the same

问题 I simulate an evolving population in Julia. Somewhere in my code I randomly sample (sample weighted by the fitnesses of the individuals) individuals in order to form the next generation. Because the same individual can be sampled several times (sampling with replacement), I have to make that I copy the individuals and not only create a new pointer to the same data. Here is what the code looks like for the moment: ##### Reproduction ###### NewPopulation = Array(Individuals, nb_individuals_in

问题 We have an application that performs comparisons on data objects to determine if one version of the object is different than another. Our application also does some extensive caching of these objects, and we've run into a bit of a performance issue when it comes to doing these comparisons. Here's the workflow: Data item 1 is the current item in memory. This item was initially retrieved from cache and deep cloned (all sub objects such as Dictionaries etc). Data item 1 is then edited, and its

问题 Suppose I have the following class: public class Author { public int ID {get; private set;} public string firstName {get; private set;} public string lastName {get; private set; } public Author(int id, string firstname, string lastname) { this.ID = ID; this.firstName = firstname; this.lastName = lastName; } public static Author Clone(Author clone) { Author copyAuth = new Author(clone.ID, clone.firstName, clone.lastName); return copyAuth; } } and public class Book { public string bookTitle