nice but is a way to get lost with your types
better of checking each eg a.car b.car c.car
It's not a suggestion of how to handle types, it's a demonstration of LOCAL variables and GLOBAL variables, nothing more than that.
besides which referring to each type by an individual variable is inefficient, since they are all of the same type, looping through them is quicker, more memory efficient and less error prone.
i.e.
for n = 1 to 5 a.car = new car a\x = n*10 ;or whatever next for a.car = each car print a\x next
instead of:
a.car = new car a\x = 10 b.car = new car b\x = 20 c.car = new car c\x = 30 d.car = new car d\x = 40 e.car = new car e\x = 50 print a\x print b\x print c\x print d\x print e\x