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kotlinlang

Is there a reason why `DefaultSwitchColors` (and similar colour interface implementations in the Material library) don’t use `data class`es and instead manually implement equals/hashcode?

Yeah, what Harsh said! Jake wrote a good article about it:
<https://jakewharton.com/public-api-challenges-in-kotlin/>

If there's a possibility that we might need to add more members to the class -- better make it non-data :slightly_smiling_face:

But `DefaultSwitchColors` isn’t a part of the public API, it’s private

The article is really interesting, thanks! Good to know why `data class`es are avoided in general in published libraries

Yep, the binary compatibility reasons are important for public API.

In this case, using data classes would just add a bunch of methods to the published libraries that we don't need, so we might as well save some method count and bytes if we can.