A leaner `Tuple` runtime with type proofs and auto...

# arrow-meta

[raulraja]

A leaner Tuple runtime with type proofs and automatic conversions coming up in Arrow Meta

[drieks]

Why not this way?

inline fun <A, B> tupled(a: A, b: B): Tupel2<A, B> =
  Tupled(arrayOf(name, age)).widen()

fun Person.tupled(): Tuple2<String, Int> = tupled(name, age)

[raulraja]

That's an option and Person.tupled can also be inlined

[drieks]

@tupled
data class Person(val name: String, val age: Int)

could generate:

typealias TupleForPerson = Tupel2<String, Int>

@proof(conversion = true)
inline fun Person.tupled(): TupleForPerson =   tupled(name, age)

@proof(conversion = true)
inline fun TupleForPerson.person(): Person {
  val (name, age) = this
  return Person(name, age)
}

[raulraja]

yes, that is our plan in arrow.generic and other places, the proofs are automatically generated for all data classes