Allow indentation inside (...)

[odersky]

Change the rules so that indentation is recognized everywhere, and
not just at the toplevel and inside braces.

[bishabosha]

Tested passing for these

def foo(x: Int) =
  var x1 = x
  List(
      if x > 0
        true
      else
        false
      ,
  while x1 > 0 do
    x1 -= 1
    ,
    while
      x1 > 0
    do
      x1 -= 1
    ,
      try
        ???
      catch
      case err =>
      finally
        println("foo"),
            for
              i <- 1 to 10
            yield
              i * 2
    ,
    for _ <- 1 to 3 do
      for _ <- 3 to 6 do
        x1 += 1
  )

[bishabosha]

Edit: it is surprising that these compile (if your mental model was indentation syntax was about column alignment, and not simply that braces are now optional)

  def foo(x: Int) =
    var x1 = x
    List(
while x1 > 0 do
  x1 -= 1
)

  def foo(x: Int) =
    var x1 = x
    while x1 > 0 do
x1 -= 1

  package example

        class Foo:
    def foo(x: Int) =
      var x1 = x
      while x1 > 0 do
x1 -= 1

[odersky]

@bishabosha Why should these examples not pass? Note that the while-do is followed by a single statement. So that compiles even without implied braces.

[bishabosha]

@odersky Those last examples I didn't compare to the previous dotty release as I was so surprised, so yes I agree now that those behave as expected.

So I suppose the feature really is optional braces, and the realm of aesthetic code alignment is left to linters