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─────UNION...END UNION──────────────────────────────────────────────────────
 
     Action
 
     Causes two or more maps to occupy the same memory location.
 
     Syntax
 
     UNION
        map-statement
        map-statement
        [map-statement] ...
     END UNION
 
     Parameter          Description
 
     map-statement      A map declaration.
 
     Remarks
 
     The UNION statement allocates the same memory area to more than
     one variable.
 
     A UNION can only appear within a STRUCTURE.
 
     The $PACK metacommand and /Zp command-line option control how
     variables in structures are assigned to beginning byte addresses.
     The particular packing option chosen may affect how particular
     variables are assigned to the same memory location.
 
     See Also: ◄MAP...END MAP►
               ◄STRUCTURE...END STRUCTURE►
               ◄$PACK►
 
     Example
 
     Note how the first 40 characters in the string2 array are
     assigned to four-byte integers, while the remaining 20 are
     assigned to two-byte integers:
 
           UNION
              MAP
                 CHARACTER*20 string1, CHARACTER*10 string2(6)
              END MAP
              MAP
                 INTEGER*2 number(10), INTEGER*4 var(10), INTEGER*2
          +      datum(10)
              END MAP
           END UNION
                                    -♦-