How to keep generic type of paramters?

[zjns]

What kind of issue is this?

• Question. This issue tracker is not the place for questions. If you want to ask how to do
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  Overflow. https://stackoverflow.com/questions/tagged/retrofit

As title say, I want to keep generic type of paramters, but I don't know how to do it, default proguard rules of Retrofit not working.
Can anyone tell me how to do this?

[JakeWharton]

It is impossible to target that with static shrinker rules. As a result, we offer https://github.com/square/retrofit/tree/trunk/retrofit-response-type-keeper