I'm having some trouble with type inference. For example, if I write: ```val myMap = mapOf("id" to 1...

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[Tianyu Zhu]

I'm having some trouble with type inference. For example, if I write:

val myMap = mapOf("id" to 10, "hash" to 99999L)

I would expect the id key to contain an Int and the hash key to contain a Long, but that's not the case-- id is now mapped to a long!
I can fix this by writing

val myMap = mapOf("id" to 10 as Int, "hash" to 9999L)

But then IntelliJ tells me that the cast is not needed.

Is there a better way?

[hho]

You could make the type of the resulting Map explicit:

val myMap = mapOf<String,Number>("id" to 10, "hash" to 99999L)

[Tianyu Zhu]

My map will have more than numbers (it's a map-representation of a struct) So I'd use map<String, Any>

But I find it very odd that Kotlin does this kind of upcasting. 😞

[ephemient]

it's not casting, it's that integer literals take on the expected type

[ephemient]

e.g. val i: Long = 10, val b: Byte = 10

[Tianyu Zhu]

Oh I see!

[ephemient]

so you could also mapOf("id" to 10.toInt(), "hash" to 9999L) to force it to be considered as an Int literal

[ephemient]

(despite looking like a function call, <literal>.toInt() etc. are treated like constant literals by the compiler)

[Tianyu Zhu]

🤯