Object-Oriented-Programming | Object Oriented Programming with C | Transpiler library

I'm going through a Python OOPs book by Dusty Phillips. I fail to understand a particular program in the book, chapter 7 - Python Object-oriented Shortcuts. The extended version of the code is available here

Although the program comes under the topic Functions are objects too, the provided program also uses a strange code, which i feel, more of imply the opposite (using objects as functions).

I have pointed out the line in the code where i have the doubt. How is that variable callback of TimedEvent used like a function Timer class ? What is going on here in this part.

I'm following freecodecamp JavaScript oop course. The course describes how you should declare a private variable inside objects for cases like passwords and bank accounts which cannot be changed from outside. the only access to private variables is through public method that has access to the private variable. then it gives this demo code to illustrate the point.

I'm currently solving the PaymentCard exercise in https://java-programming.mooc.fi/part-4/1-introduction-to-object-oriented-programming and the output of this program should not be a negative balance. If ever the balance gets negative, it will not be printed. I added a conditional statement in both methods but my output keeps printing a negative balance.

Any help would genuinely be appreciated. Thanks!

I am surprised that my question was not asked (worded like the above) before. I am hoping that someone could break down this basic term "object" in the context of a OOP language like Python. Explained in a way in which a beginner like myself would be able to grasp.

When I typed my question on Google, the first post that appears is found here.

This is the definition: An object is created using the constructor of the class. This object will then be called the instance of the class.

Wikipedia defines it like this: An object is an instance of a Class. Objects are an abstraction. They hold both data, and ways to manipulate the data. The data is usually not visible outside the object.

I am hoping someone could help to break down this vital concept for me, or kindly point me to more resources. Thanks!

I am using NDepend for code analysis and got this warning:

https://www.ndepend.com/default-rules/NDepend-Rules-Explorer.html?ruleid=ND1901#!

This rule warns about static fields that are not declared as read-only.

In Object-Oriented-Programming the natural artifact to hold states that can be modified is instance fields. Such mutable static fields create confusion about the expected state at runtime and impairs the code testability since the same mutable state is re-used for each test.

My code is as follows:

i have been learning a roblox lua language and many times i have came across something called table has a state like objects line and i really don't understand that as i don't how to visualize it,like what it actually means

i have been reading this roblox lua article and have came across this line again: Object-Oriented Programming(https://developer.roblox.com/en-us/articles/Object-Oriented-Programming)

this is some bit of that article and it contains that line:

As Lua supports duck typing through the use of Metatables, the ability to create “objects” can be achieved. This is essentially objected-oriented programming. A Tables in Lua is an object in more than one sense. Like objects, tables have a state. Like objects, tables have an identity that is independent of their values; specifically, two objects (tables) with the same value are different objects, whereas an object can have different values at different times, but it is always the same object. Like objects, tables have a life cycle that is independent of who created them or where they were created.

can somebody help me with this i have been trying search this on google but nothing similar shows up,like what actually it is?also what do we mean by tables as objects?

I've been working with ruby for quite a while now and I am kind of stuck using an object oriented approach. I have read things about objects, classes, the solid principles and some tutorials but these often come up with only one single class, like in this intro (scroll to the very bottom of the page).

Here's the example from the linked website.

My question is how I can implement another class, let's say a Client best?

I'm new to OOP PHP, so, past week i was searching for a simple tutorial to enter in this new world and I found a good one from Codecourse(Codecourse OOP PHP Login/Register System), but in the 14th video, I got an error that I couldn't solve or find the problem, anyone quem help me?

This is the error:

Fatal error: Uncaught Error: Call to a member function count() on bool in D:\Rafael\xampp\htdocs\sywork\classes\Validate.php:37 Stack trace: #0 D:\Rafael\xampp\htdocs\sywork\register.php(9): Validate->check(Array, Array) #1 {main} thrown in D:\Rafael\xampp\htdocs\sywork\classes\Validate.php on line 37

This is the link for the my code: My Code

This is the link for the complete code(isn't mine): Complete Code

Here is the archives that I keep getting errors:

I have been trying to understand the type system for Julialang but some design aspects are still confusing me. I was hoping someone could clarify.

So the question here is about Abstract Types and their concrete implementations. From what I understand Julia Abstract types do not enforce any constraints on their concrete implementations. So there is no guarantee that a method that works on the Abstract type will work on a concrete implementation of that type.

I get that Julia does not use classes or follow inheritance. But I just want to avoid generating all sorts of bugs in my code. If there is a different design paradigm, then could someone please answer question 2 below.

So I have 2 questions.

1. Is this still the way that the language works? Just to confirm nothing has changed since the blog post.

2. How do users design their software around this seeming vulnerability?

And example of the issue from the linked post: