List and Class

Monkey Forums/Monkey Programming/List and Class

tagoror

(Posted 2011) [#1]

Hello,

In Blitzmax we can write an estructure like this:

Type Tobj

field x : float
field y : float

...

End Type

... and to create derived types:

Type Tplayer extends Tobj

...

End Type

Type Tenemy extends Tobj

...

End Type

Suppose we have added all the objects created to a list called myList.
BlitzMax access all the objects added to the list in this way:

For o : Tobj = Eachin myList

.....

Next

If you want to access Tplayer objects we can wrote:

For o : Tplayer = Eachin myList

....

And if we access the Tenemy objects we can wrote:

For o : Tenemy = Eachin myList

----------------------------------------------------

In Monkey, we create the base class:

Class Tobj

....

End ' Tobj

And after that, the derived classes:

Class Tplayer extends Tobj

....

End ' Tplayer

Class Tenemy extends Tobj

.....

End ' Tenemy

To access to all Tenemy and Tplayer objects ....

Local myList := New List <Tobj>

For Local o := Eachin myList

o.render()

Next

... but, here is my question. How can I access from Monkey
to all Tenemy objects only?

For local o ... ?

Thank and kind regards,

Tagoror

GW_	(Posted 2011) [#2]

You can promote the object inside the loop.

For Local o ...
	If tEnemy(o) Then
	  'Its of tEnemy
	Else
	  ' its not
	Endif
Next

I'm not sure if all the target languages support the type of casting that BMax eachin does.

ziggy

(Posted 2011) [#3]

All target languages, but take into account that Arrays ore Strings are not objects in Monkey.

tagoror

(Posted 2011) [#4]

Thank you for the information. I'm going to test it.