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Get field names of case class using shapeless
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import $ivy.`com.chuusai::shapeless:2.3.3` | |
import shapeless._ | |
trait Fields[T] { | |
def fields: List[String] | |
override def toString: String = fields.mkString(", ") | |
} | |
object Fields extends LabelledProductTypeClassCompanion[Fields] { | |
def apply[T](fs: List[String]): Fields[T] = new Fields[T] { | |
override def fields: List[String] = fs | |
} | |
implicit val string: Fields[String] = apply[String](Nil) | |
implicit def anyVal[T <: AnyVal]: Fields[T] = apply[T](Nil) | |
implicit def hkt[F[_], T]: Fields[F[T]] = apply[F[T]](Nil) | |
object typeClass extends LabelledProductTypeClass[Fields] { | |
override def product[H, T <: HList](name: String, ch: Fields[H], ct: Fields[T]) : Fields[H :: T] = | |
Fields(name :: ct.fields) | |
override def emptyProduct : Fields[HNil] = Fields(Nil) | |
override def project[F, G](instance: => Fields[G], to: F => G, from: G => F) = Fields(instance.fields) | |
} | |
} | |
case class Foo(bar: String, baz: Boolean) | |
println(implicitly[Fields[Foo]].fields) |
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