Allow named tuple syntax for case class constructors. #22400
Conversation
A test case that shows that we can have an "inline type class" that allows to use a typeclass-based scheme for sequence literals where instances can be created with macros.
Also: Move test to run
We now don't try to instantiate selected type variables. Instead, we use a default as fallback if the expected type is underspecified according to the definition in Implicits. This is simpler and more expressive.
Also, test infix operations taking [...] as a right operand.
This is a tweak to the named tuple spec. If the expected type is a case class expand to a call of its apply method.
| val anotherLit: IArray[Double] = [math.Pi, math.cos(2.0), math.E * 3.0] | ||
| val diag: Array[Array[Int]] = [[1, 0, 0], [0, 1, 0], [0, 0, 1]] | ||
| val empty: ArrayBuffer[Object] = [] | ||
| val mapy: HashMap[Int, String] = [1 -> "one", 2 -> "two", 3 -> "three"] |
There was a problem hiding this comment.
I more like Dartlang's syntax for this, here, [] is an Array, which makes me think the KEY can be REPEATED, but actually, it isn't.
val mapy: HashMap[Int, String] = [1 -> "one", 2 -> "two", 3 -> "three"] can be
val mapy: Array[(Int, String)] = [1 -> "one", 2 -> "two", 3 -> "three"]
but if you chose Dart's syntax, then the HashMap[Int, String] can be omitted.
val mapy = {1 -> "one", 2 -> "two", 3 -> "three"} is a map or
val mapy = {1 : "one", 2 : "two", 3 :"three"} is a map too.
There was a problem hiding this comment.
When all are [], you lose the information of if the element or key can be repeated, and then you have to annotate the result type explicitly, which is not how Scala's works, a well static typed language as a dynamic language, and now, with [] everywhere, we are writing plain old Java.
This is a tweak to the named tuple spec and implementation. If the expected type is a case class,
expand a named tuple to a call of the apply method of the case class.
Based on #21993. Only the last commit is relevant.