Variance... without Generics!

Did you know that you can use covariance and contravariance in Kotlin without generics?  Unlock the mental model of generic variance by first understanding how variance works with regular type hierarchies!

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00:00 Introduction
00:35 Upholding the Contract in Subtypes
02:05 Covariance
04:12 Contravariance
06:54 Summary of Variance
07:15 Why Generic Variance Works
08:10 Wrap-up

#kotlin #androiddevelopment