Allow continue statement inside a switch with specific case instruction

[samuelgozi]

Add new syntax to the continue statement that would allow it to jump to a specific case in a labeled switch.

This could improve performance by avoiding unnecessary failed branch predictions, and makes the code easier to follow.

Edit: I also think that this is a better option, possibly a replacement to fallthrough, which requires the cases to be ordered in a specific way, and even then is very limited. This syntax allows precise control flow, with goto performance but in a controlled setting.

Example:

package main

State :: enum {
  A,
  B,
  C,
}

// Continue with state argument
main :: proc() {
  state := State.A

  parser: switch (state) {
    case A:
      continue parser .B
      // or alternatively
      continue .B
    case B:
      // Continues from here
    case C:
      // do something
  }
}

// Better than this
main :: proc() {
  state := State.A

  for {
    switch (state) {
      case A:
        state := State.B
        continue
      case B:
        // do something
      case C:
        // do something
    }
  }
}

[gingerBill]

I've considers this approach numerous times and the answer is no.

1. it should be fallthrough not continue.
2. The for loop is honestly clearer to read too, and is most cases people want something like this, they are pretty much always iterating too
3. It's a weak form of computed goto and not necessarily a good idea for Odin.