Types and polymorphism

After reading John Judnich's great tutorial on OOP and BlitzMax, I though i had finally got round my head round the subject. Alas, no, hence I'm appealing for help... I have a type, TEntity that is Extended by THuman. The field "somevalue" is set in TEntity. I have some very simple code:

Local human:THuman=New THuman
Local entity:TEntity
entity=human

Can someone explain why the values of human.somevalue and entity.somevalue are different?

Thanks, a confused Welshman.

Well, without seeing your code, I don't know if this is the problem or not, but I'm guessing that you are redefining somevalue in THuman.

Try copying and pasting this and you'll see it works...

Strict

Type Entity
Field SomeValue:Int

Method New() 
SomeValue = 55
EndMethod

EndType

Type Human Extends Entity

EndType

Local Hum:Human = New Human
Local ent:Entity
ent = Hum

Print "Ent.Somevalue = " + ent.somevalue
Print "Hum.SomeValue = " + hum.somevalue

However, if you change type human to the following, it won't work.

Type Human Extends Entity
field SomeValue:int
EndType

In this case, you've redefined SomeValue in type Human, and this redefined value is NOT set in the base class New() method.

I think that is the problem. I thought I could "overload" the field, but obviously not.

Thanks for your help!