Like Variables, structures do not need to be declared.
Sub-elements of a structure can be any of these variable types:
Integer
Double
Point
Feature Pointer
Function
Array
Structure
For example, it is possible to have structure elements that are arrays and array elements that are structures. This makes the following example expressions valid:
ASSIGN/CAR.LEFTSIDE.DOOR[2].QUADRANT[3].JOINT[5].HIT[4]=MPOINT(558.89,910.12,42.45)
COMMENT/OPER,"Current Z Position: "+CAR.LEFTSIDE.DOOR[2].QUADRANT[3].JOINT[5].HIT[4].Z
ASSIGN/CURRENTJOINT=LEFTSIDE.DOOR[2].QUADRANT[3].JOINT[5]
COMMENT/OPER,"Next Hit: "+CURRENTJOINT.HIT[4]