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Is there any public benchmark of `typeOf` (1.8+, preferable)? I know it will be slower than a direct access to `Type::class` but *how much slow* will it be? :thinking_face:

Reference: <https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.reflect/type-of.html|https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.reflect/type-of.html>

But why would you need typeOf if you already have access Type::class?

typeOf is useful when you need KType with generic information. So even if it 2-3 magnitude slower you not always can replace it
If your code is performance sensitive you probably want to measure it yourself for your own case

Thank you for your answer <@U0BRK9HC5>!

To be fair, my question is more for learning purposes than a real use case - but I was envisioning retaining generic info as you described.

Just for matter of example, let's say we are developing a KMP DI/SL which the type passed in can have generic info (but not always), and the DI/SL would return an instance. Normally, the approach would be to use a KClass to find the correct instance provider but with KType we could retain the generic info and differentiate same class with different generics without custom qualifiers - which would be really nice to have. On the other hand, a DI/SL could map a really big quantity of classes, so I wonder if the performance impact would be problematic and I was wondering if JetBrains would have benchmarks for typeOf.

An alternative use would be to check if there is `typeParameters` and deciding by using KClass or KType based on the need. Not sure how better that would be.

Does that make any sense?

If I would like to differentiate by generic on level of DI, I would use KType, otherwise KClass, even if performance-wise it’s similar
At least it would be more explicit

Thank you for taking the time to answer, I super appreciate. It makes sense. :hugging_face:

fair enough :+1: Perhaps by having secondary API for generics call, wouldn’t impact the “core” features performances but we would open to things for generics