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Can generic parameters be reified at class level?
<https://discuss.kotlinlang.org/t/can-generic-parameters-be-reified-at-class-level/13791>

I read somewhere (can't find it now), there is a vague-ish plan for this feature, but there are a lot of questions to answer, like which class loader does the generated class belong to and other stuff. I'll post a link when I find it.

I've walked around this in the passed using an interface and a reified constructor function. But might depend on the use case if that'll work for you or not.

This is one of the links <https://discuss.kotlinlang.org/t/reified-type-parameters-in-classes/1567/5> .

Untitled

Example of how to walk around it using `interface` &amp; `reified fun`.

<@UDN1U8ZD1> Please follow the channel topic:
&gt; All discussion in this channel should begin with a use-case or proposal instead of a question.

<@U10EJRH2L> I've phrased it as a question, but it *is* a proposal (the linked post is mine). I wanted to get feedback both here and there, so instead of copying over the whole post, I just put up a link to the forum thread. This way, people here who are interested enough to click on the link will be able to read not only the content, but also the discussion on the forum.

And I really recommend that the discussion be read, because already (as of two commentators), the idea's becoming a bit more crystallized by prompting me to think of things I hadn't thought of before.

<@U0RM4EPC7>
Yes, `inline reified` constructor functions are very useful sometimes, but the methods of the generic class still don't have access to the type parameter. For that you'd _have_ to inline the whole class.

<@UBJF87EBY>
Please do. Would be most welcome.

In the example I gave I use it the `reified A`  in a method?

<@U0RM4EPC7>
Oh, I'm sorry, I didn't catch that before. Yes, you're right. In fact I'm using this very approach right now in what I'm working on (details in the forum thread comments). But you're actually manually inlining the type. My question is (and I know this is a very selfish question to ask), can't the compiler do that? For my example I had to do this inlining for about a hundred classes (don't ask:sweat:)  which are all implementations of a generic base class, all with different `T`s.

Ouch :confused: Yes, that’s indeed required. I don’t think it’s a selfish thing to ask, I have needed this from time to time when inter-opting with Java libs.

<@U0RM4EPC7>
I actually used regular expressions to generate all those inline implementations, so wasn't too hard. But looking at and maintaining 3000+ lines of code which consists of the same repetition is the hard thing.