Understanding Typescript's views on inheritance

Question

I have been struggling to understand the reasons why typescript developers choose the way they implemented inheritance.

What I would expect from any language supporting inheritance is these order of work:

1. The derived class initialized properties are initialized
2. The base class initialized properties are initialized
3. The base class constructor runs
4. The derived class constructor runs

What apparently happens:

1. The base class initialized properties are initialized
2. The base class constructor runs
3. The derived class initialized properties are initialized
4. The derived class constructor runs

I don't yet understand what kinds of benefits come from implementing this kind of inheritance

My question boiling down to this:

What kinds of projects makes this implementation of inheritance perfect for?

EDIT: relevant link to discussion: https://github.com/Microsoft/TypeScript/issues/1617

• gnat: see Why do 'some examples' and 'list of things' questions get closed?
• dagnelies: I don't understand the close vote, it looks both like a legitimate and even interesting question to me. ...*maybe* the reason is related to some JavaScript constraints / compatibility issues.
• dagnelies: @user108589: your EDIT github link pretty much summarizes the reasoning behind it. There you have your answer.
• Jörg W Mittag: @dagnelies: the question asks for a list of projects (or more precisely, for a list of kinds of projects). List questions are off-topic. The interestingness of the question is irrelevant. There are lots of things that are of interest, but not on-topic.
• Frank Hileman: It is more than simply following the protocol of another language. The order of initialization ensures that pre-conditions and invariants in the base class are satisfied before the derived class begins execution. This is important for proving correctness.