Apply method with curly braces

Question

Why this works:

  List(
   \"string\", \"string2\"
  )

But this doesn\'t?

  List{
   \"string\", \"string2\"
  }


        

Answer 1

Canonical answer on braces and a supplement.

The official glossary helpfully calls a block an encapsulation of side effects and a result value.

A few opinions were recently expressed on the ML about braces and their non-pointy cousins.

Perhaps it is unhelpful to think of parens and braces as somehow interchangeable in some contexts.

It is easier to think in terms of exprs and blocks, and in this case, function args can be either comma-separated exprs or a block.

Answer 2

The difference is in the comma -- you can only have a comma separated argument list when using parentheses.

You will find that

List {
    3
}

works just fine.