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Hi there. Any protips, why is the compiler (1.7.21, JVM) complaining about “No cast needed”, when it is in fact required, because otherwise there’s `Int`/`Long` ambiguity?

Because a short number alone is always considered to be an Int, if you want to explicitly return a Long, you can write `123L`

<https://kotlinlang.org/docs/numbers.html#literal-constants-for-numbers|https://kotlinlang.org/docs/numbers.html#literal-constants-for-numbers>

that documentation doesn't cover everything. a bare literal integer can be either an `Int` or a `Long`

see <https://kotlinlang.org/spec/type-system.html#integer-literal-types> for more details

this has been an issue with `sumOf` for as long as it has existed, <https://youtrack.jetbrains.com/issue/KT-46360>

I understand the reason for need to specify Int as return type here, but I don't know why compiler complains when I do it :slightly_smiling_face:

<https://youtrack.jetbrains.com/issue/KT-50177> the quick fix is wrong (this should be a KTIJ bug since that's where the problem comes from)

as a workaround, you can write `0.toInt()` instead of `as Int` to force the type, but the KTIJ plugin will (falsely) show that as unnecessary too :disappointed:

No, the problem exist on gradle build log as well, so it's not IJ specific.

hmm I don't see the message in the kotlin compiler source, maybe it's a different one…

```❯ ./gradlew clean build

&gt; Task :compileKotlin
w: /Users/jakub.gwozdz/personal/advent-of-code-2022/src/main/kotlin/day2/Day2.kt: (33, 11): No cast needed
w: /Users/jakub.gwozdz/personal/advent-of-code-2022/src/main/kotlin/day2/Day2.kt: (49, 11): No cast needed```
:slightly_smiling_face:

ah, that makes it easy to find then. a `@Suppress("USELESS_CAST")` will stop that from showing up

yes that’s what I did, but I was wondered why is it like so. Apparently it’s a known bug/problem, so I’m ok with that :slightly_smiling_face:   Thanks for the help and the links

In any case, why bother with such code when you can do `lineSequence().count { it == "one" }`?

that was just the `foo()` example :slightly_smiling_face: