MODE CP = STRUCT (PROC VOID inc, PROC INT read);
PROC cc = CP: (INT count := 0; (
  (VOID: count +:= 1),
  (INT: count)));

# Demo: #
CP c1 = cc, c2 = cc;
  inc OF c1; inc OF c2; inc OF c1;
  print((read OF c1, read OF c2))

# => a68g: runtime error: 1: value is exported out of its scope (detected in PROC 
VOID closed-clause starting at "(" in this line). #