Scala.js Support

Basically, record4s works fine in Scala.js because it is mostly written in pure Scala code. Sometimes you may wish to use records with native JavaScript code and that will require some additional mechanism.

Converting a Record from / to a Native JavaScript Object

You can use fromJS and toJS to convert a record from/to a native JS object.

import com.github.tarao.record4s.%
import scala.scalajs.js

val obj: js.Any = js.Dynamic.literal(name = "tarao", age = 3)

// convert obj to a record
val r = Record.fromJS[% { val name: String; val age: Int }](obj)
// val r: %{val name: String; val age: Int} = %(name = tarao, age = 3)

// convert the record again to a JS object
val j = r.toJS
// val j: js.Any = [object Object]

Converting a Record from / to a JSON string

Methods fromJSON and toJSON convert a record from/to JSON string internally using JSON.parse and JSON.stringify.

import com.github.tarao.record4s.%

val json = """{"name":"tarao","age":3}"""

// convert a JSON string to a record
val r = Record.fromJSON[% { val name: String; val age: Int }](json)
// val r: %{val name: String; val age: Int} = %(name = tarao, age = 3)

// convert the record again to a JSON string
val j = r.toJSON
// val j: String = {"name":"tarao","age":3}

Converting Nested Types

All these conversions described above support nested types.

val r = %(
  name = "tarao",
  age  = 3,
  email = %(
    local  = "tarao",
    domain = "example.com",
  ),
)
val json = r.toJSON
// val json: String = {"name":"tarao","age":3,"email":{"local":"tarao","domain":"example.com"}}

It is also possible to convert a type in which a record type appears as a nested type. In this case you have to use native-converter directly.

import org.getshaka.nativeconverter.fromJson

val json = """[{"name":"tarao","age":3}]"""
val seq = json.fromJson[Seq[%{ val name: String; val age: Int }]]
// val seq: Seq[%{ val name: String; val age: Int }] = List(%(name = tarao, age = 3))

import org.getshaka.nativeconverter.NativeConverter.SeqConv

val s = Seq(
  %(name = "tarao", age = 3),
  %(name = "ikura", age = 1),
)
// val s: Seq[%{val name: String; val age: Int}] = List(%(name = tarao, age = 3), %(name = ikura, age = 1))
val json = s.toJson
// val json: String = [{"name":"tarao","age":3},{"name":"ikura","age":1}]

If you have your own class, you have to provide a given instance of NativeConverter[_] for that class. See the documentation of native-converter for the detail.