DATA TYPE MYINT IS INT:
-- This next line falls in the category of awkward things to parse.
-- The problem is that:
--   PROC copy.MYINT (VAL MYINT x, MYINT)
-- would be a perfectly legal (if silly) thing to say, so we have to make
-- sure we try this interpretation first:
PROC copy.MYINT (VAL MYINT x, MYINT y)
  y := x
:
PROC P ()
  MYINT a, b:
  SEQ
    a := 42
    copy.MYINT (a, b)
    ASSERT (b = 42)
: