swift234

Implement trailing closure syntax.

Trailing closure syntax allows one to write a closure following any
other postfix expression, which passes the closure to that postfix
expression as an arguments. For example:

        sort(fruits) { |lhs, rhs|
          print("Comparing \(lhs) to \(rhs)\n")
          return lhs > rhs
        }

As a temporary limitation to work around the ambiguity with

  if foo { ... } { ... }

we require trailing closures to have an explicit parameter list, e.g.,

  if foo { || ... } { ... }



Swift SVN r5210