I've had a search through the history of this chan...

# arrow

[kushalp]

I've had a search through the history of this channel but couldn't find anything. I have the following map mapOf("foo" to "2") . I want to convert it into the following data class data class Sample(val foo: Option<Number>) . I know I can use jacksonObjectMapper to do this if I wasn't using Option using fun fromMap(m: Map<String, String>) = jacksonObjectMapper().convertValue<Sample>(m) . How can I get jacksonObjectMapper to convert any values I have into Option ? Providing a None value for nulls.

[Bob Glamm]

I thought maybe this was present in Arrow, but I think the best option you have currently is to pull something like this in scope:

fun <T> T?.asOption(): Option<T> = Option.fromNullable(this)

[raulraja]

I guess for that case you would have to write a custom marshaller for jackson for Option but I wouldn’t recommend it since nullable types should already be supported and they are isomorphic to option and faster, as Bob said you can always go toOption when you need to.

[raulraja]

@kushalp actually… https://github.com/arrow-kt/arrow-integrations/blob/1fb60ff9bcf8866da77ad9d9ce7757a6698b8541/arrow-integrations-jackson-module/src/main/kotlin/arrow/integrations/jackson/module/OptionModule.kt

[raulraja]

Looks like we already have that thanks to @Alpha Ho

[kushalp]

Cool. How do I use that module?

[kushalp]

Do I need to import something additional when using arrow-core:0.10.4 ?

[kushalp]

@raulraja ☝️ ?