RFC #22: Should accumulative for expressions remain in the language?

[ProCode-Software]

• These allow assignment operators such as += to be used in for expressions to accumulate a value instead of creating a new list. (reduce)

  items := [1, 2, 3, 4, 5, 6]
  sum := for item in items += item
  

• Should for expression blocks remain in the language?
  
  These allow a new list to be created by returning values, also allowing control flow such as next and stop. (filter)

  numbers := [1, 2, 3, 4, 5, 6]
  evenNumbers := for num in numbers {
      when item % 2 {
          0 -> return item
          _ -> next
      }
  }