COBCH1671 Not a valid dictionary iterator

The key or value phrase of the perform syntax has been specified on a collection that is not a valid dictionary.

In the following example, the key phrase is specified on a list, not a dictionary. You must either remove the key phrase to perform the iteration, or change the definition of myCollect to a dictionary.

...
declare myCollect as list[string]
perform varying key s as string through myCollect
  display s
end-perform
...