Stack Overflow
Stack Overflow

Questions tagged [downcast]

Downcasting permits an object of a superclass type to be treated as an object of any subclass type.

589 questions
0
votes
0 answers

TypeError: "method is not a function" error when downcasting to a subclass - discrord.js

Please, don't mind my grammar and code mistakes because I am a self-taught coder I am developing a multi-purpose Discord bot with NodeJS using discord.js and typescript libraries. When creating the ticket system, and trying to make it as universal…
DeMineArchiver
  • 36
  • 2
  • 6
0
votes
1 answer

Downcast trait to generic type

I have the following 2 traits: Org, Capability. #![feature(specialization)] trait Org {} struct OrgV1 {} impl Org for OrgV1 {...} struct OrgV2 {} impl Org for OrgV2 {...} trait Capability {} struct CapV1 {} impl Capability for CapV1…
Aibek
  • 318
  • 3
  • 11
0
votes
1 answer

DownCasting in generics in java

I am stuck in generics downcasting. Because I learn type erasure. When code compiles all parameterized types are converted to the upper bound if the bound is not defined then it changes to object. Gen Class public class Gen { T ob; …
AhmadRaza
  • 5
  • 6
0
votes
0 answers

Dealing with int dtypes while using .values() in pandas

I have read the documentation: https://pandas.pydata.org/docs/reference/api/pandas.DataFrame.values.html My df has a mix of strings, objects and int dtypes. I have not found a way to control for using .values() on my df without having to reconvert…
Clay Campbell
  • 168
  • 13
0
votes
2 answers

Example of useful downcast with static_cast which does not produce undefined behaviour

I am wondering about a short code example of an application of downcast via static_cast, under conditions where there is no undefined behaviour. I have looked around and I found quite a few texts (posts, Q&A, etc.) referring to fragments of the…
sancho.s ReinstateMonicaCellio
  • 14,708
  • 20
  • 93
  • 185
0
votes
0 answers

Downcasting a CompletableFuture's object type - Java/Spring Boot

I have the following classes: public class AccountDetail { private String accountNumber; private Date effectiveDate; private String status; // a bunch of other properties } public class AccountDetailWithAlerts extends AccountDetail…
apex2022
  • 777
  • 2
  • 8
  • 28
0
votes
2 answers

How do I access setter of a subclass without downcasting in my Java code?

I'm pretty new to programming, so please bare with me. I have made a Class Car through composition with an instance variable movable : CarMovable. The CarMovable abstract class is not included here but I have made subclasses from it (since cars…
hi there
  • 35
  • 3
0
votes
0 answers

How can I cast a Int type value coming from a web service to a String type?

When I receive data from a json I stored inside an array so that I can iterate that array and store each value inside a dictionary type and assign each value using the dict key, the problem is that one of the values is an INT type, if I try to…
Angel Davila
  • 75
  • 7
0
votes
1 answer

C++ derived-class members after downcasting

I recently learned about upcasting and downcasting in C++. However I came up with a few questions during reading about downcasting. Say I have two classes class Base { public: virtual void foo() {} }; class Derived : public Base { public: …
jleng
  • 55
  • 1
  • 7
0
votes
1 answer

Downcasting an implementation using an interface template

I'm implementing a generic interface that can bridge different implementations of some base class. The interface utility is written as follows: // InterfaceUtils.h // // Base object class class IBaseObject { virtual ~IBaseObject() =…
Martin
  • 141
  • 1
  • 11
0
votes
1 answer

How to avoid downcasting on nested properties (not methods)

I'm coding an API to import data into our software. As you can see below my models hierarchy is broken down into different types of models (A & B). Each model : embed another model : "ImportModel" embed "Production" which embed "Parts" Ex :…
Daftom
  • 1
  • 2
0
votes
1 answer

C++ Inheritance & Virtual Functions Where Base Parameters require Replacement with Derived Ones

I have looked high and low for answers to this question - here on this forum and on the general internet. While I have found posts discussing similar topics, I am at a point where I need to make some design choices and am wondering if I am going…
Jason
  • 3
  • 2
0
votes
2 answers

Is there a way to down cast a struct to its derived one in C++?

Here is my situation: struct A { int numberAllChildStructsUse; } struct B : A { std::string strUniqueToB; } struct C : A { std::string strUniqueToC; } (in some source file) B b = thisFunctionReturnsBOrCStructsAsTypeA(int…
dmscs
  • 255
  • 2
  • 12
0
votes
2 answers

Treating a forced downcast to 'SCNView' as optional will never produce 'nil'

Starting with swift 4.2, an error appears. In previous versions the code works fine (swift 3, 4). How to write this code correctly now? swift4 swift4.2 class GameViewController: UIViewController { var scene: SCNScene! var scnView: SCNView! override…
dmitrique
  • 1
  • 1
0
votes
1 answer

How to make a drag and drop viewmodifier accept any object

I have created a drag-and-drop viewmodifier that works as expected, but now I would like to make it accept any object. I can add to all the functions, structs, and view-modifiers, but when I try to do add it to my singleton class,…
lmunck
  • 505
  • 4
  • 12
1 2 3
…
39 40