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can someone explain what i need to put into that s...
# serialization
l
can someone explain what i need to put into that string? the docs say 
a unique name of the type that is being serialized
but i dont understand what that means also why does Line 2 work but Line 3 break ?
Untitled.cpp
e
because you've defined an external serializer, there is no 
Fruit.Companion.serializer()
, so the reflection-based serializer lookup doesn't work
Box works because it is statically referring to the serializer
Json.encodeToString(FruitAsIntSerializer, Fruit.Apple)
will work
l
any other way to make this work? would it help to use the compaion object as the custom serializer ? or sth similar ?
e
as the kotlinx.coroutines docs say, you cannot write your own Compaion.serializer()
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val json = Json {
    serializersModule = SerializersModule {
        contextual(FruitAsIntSerializer)
    }
}
json.encodeToString(Fruit.Apple)
also works
l
Copy code
companion object {
	fun serializer() = FruitAsIntSerializer
}
this seems to work as well, though im not sure if i should rely on that
there are still so many things i dont understand 1. what is the string in the primitive descriptor for ? 2. why is there a reflection based lookup when the library advertises itself as reflectionless ? 3. what is the point of specifying the serializer in the annotation if it cant be looked up from there?
e
seems to indicate to me that defining your own 
fun serializer()
is explicitly not supported
l
You cannot define your own function 
serializer()
on a companion object of a serializable class
well apparently i can lol
e
1. there are formats that will use the serialName 2. that function you're calling uses reflection. there are others that don't. 3. it gets automatically used as the serializer by other 
@Serializable
-generated serializers
well apparently i can lol
for now… no guarantees.
l
so if i understand correctly, the 
@Serializable
annotation generates the function in the companion object. then shouldnt it also generate 
fun serializer() = FruitAsIntSerializer
when i use 
@Serializable(FruitAsIntSerializer::class
?
e
it actually will, in future versions, but not yet
l
welp, guess im just gonna hope that 
fun serializer() = FruitAsIntSerializer
keeps working until its getting autogenerated
e
l
oh it got merged already, guess we'll see it very soon then ?
e
in the meanwhile, I just realized that you just need public properties, so
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enum class Fruit constructor(val serializedForm: Int) {
    Apple(1),
    Banana(2)
}

@Serializer(forClass = Fruit::class)
object FruitAsIntSerializer : KSerializer<Fruit>
will work too
plugin.serialization is versioned and released with the Kotlin compiler itself (not with kotlinx.serialization), so... next version of Kotlin, I expect
BTW, your 
deserialize
function is bad: 
Json.decodeFromString<Fruit>("2")
will fail
you need to make sure to call 
decodeInt()
exactly once
l
@Serializer(forClass = Fruit::class)
didnt work
next version of Kotlin
darn 
Json.decodeFromString<Fruit>("2")
 will fail
as its supposed to, since 
2
is an invalid value
no wait you're right, ty for the hint
e
err, nevermind the 
@Serializer(forClass =)
suggestion, that doesn't get looked up the way I thought it did
l
do you think it will be added to the next minor version of kotlin, or do i have to wait for 1.6 ?
...guess its in the 
master
branch already, dont think they'd do that if it's for 1.6
e
it's in master so 1.5.20 or 1.5.30 (I haven't checked where the release train is)
l
then i should be fine using the workaround i found. ty 4 ur help
e
I don't see it in 1.5.20-RC so possibly 1.5.30
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