Does subclassing int to forbid negative integers break Liskov Substitution Principle?

In Python 3, I subclassed int to forbid the creation of negative integers:

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What’s the right data structure to combine iteration of key-value pairs, and iteration of values

I'm looking for a pre-existing or easy-to-build data structure available in Java, which can do ...

Can you implement “object-oriented” programming without the class keyword?

Say we want to provide an abstraction of an "account" in a bank. Here's one ...

Should I prefer composition or inheritance in this scenario?

Consider an interface:

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Inheriting and storing objects that contain different types of other objects

To start off, this is more of a best-practice question than anything.

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Deserializing an object at beginning of program which is used (much) later

I am writing a program, where in the beginning of the execution, I am instantiating ...

Ways to avoid using switches to map strings to classes

I have a C# solution that reads records from a db and processes them into ...

“Correct” way to use inheritance

Within a small project, a class Storage is meant to store any type of Item. ...

Inefficient use of interfaces in OOP (C#)

In my code, I've got two interfaces, let's say IOpenable and IExaminable. IOpenable allows the ...

How to reference one object with two interfaces? [duplicate]

This question already has answers here: Empty interface to combine multiple interfaces (4 answers) Closed ...