Create function inside another function

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Bee	(Posted 2012) [#1]

Note: Health is gained from Entity

A - This works

Local Enemy1:TEnemy = TEnemy.Create()

Print Enemy1.Health

B - This does not

Function EnemySpawn()
Local Enemy1:TEnemy = TEnemy.Create()
End Function

EnemySpawn()

Print Enemy1.Health

Why can't I do B?

SLotman

(Posted 2012) [#2]

Because enemy1 is local - it only exists inside the EnemySpawn funcition.

You should do:

Function EnemySpan:TEnemy()
   Local enemy1:TEnemy = TEnemy.Create()

   return enemy1
End Function

Local newEnemy:TEnemy = EnemySpawn()

Print newEnemy.Health

Or even

Print (EnemySpawn()).Health

Bee	(Posted 2012) [#3]

Creating the spawn outside of the Function would defeat the purpose of the Function in the first place though.

I'm trying to write a function that will spawn 1-16 enemies and assign them properties that can be accessed outside of the function.

I mean.. I can do it the ugly way, but trying to be nice and clean
here.

Your post gave me a couple ideas though, so thanks for that.

Last edited 2012

Last edited 2012

Midimaster

(Posted 2012) [#4]

this is easy... you can add them to a list, where all members of the type enemy are collected:

Global List:TList=New TList

Type TEnemy
	Field Health%
End Type

EnemySpawn()

For Local locEnemy:TEnemy = EachIn List
	Print locEnemy.Health
Next
End


Function EnemySpawn()
	Local Enemy1:TEnemy = New TEnemy
	' Local Enemy1:TEnemy = TEnemy.Create()
	Enemy1.Health=123
	List.AddLast Enemy1
End Function

Bee	(Posted 2012) [#5]

Thank you again Midi

I was thinking a bit too far outside the box there.

OOP > me so far

Thank you guys.

Bee	(Posted 2012) [#6]

Well. That helps me create the function,

but how would you create a dynamic number from a random number of enemies without doing Enemy1, Enemy2, etc etc.

Psuedo code:

x = Rand(1,16) 'This would be my number of enemies I want

if x = 1

Function EnemySpawn()
Local Enemy1:TEnemy = New TEnemy
' Local Enemy1:TEnemy = TEnemy.Create()
Enemy1.Health=123
List.AddLast Enemy1
End Function

else if x = 2

???

Would I have to create 16 versions of EnemySpawn()

I'm not opposed to that, just making sure I'm doing it the best way.

Corum

(Posted 2012) [#7]

EnemySpawn() should create a local instance for a New TEnemy, then once initialized it properly, should add it to the global list.
The local object reference is dropped once the scope goes out from the Function, but the global List will keep a reference to it until the object is explicitely destroyed.

EDIT: It's what it actually does, so you don't need to change it. :-)

After that, to access each Enemy you'll have to browse the list using the For..Each iterator.
Try to do it yourself and You'll learn a lot of things.
Enjoy your coding. :-)

EDIT#2: Just like Midimaster suggested.

This is officially my useless post ever in this forum! :-D

Last edited 2012

Bee	(Posted 2012) [#8]

Nice, thanks for the hints.

I really do like figuring stuff out myself, but some concepts are a bit alien without direction.

I think once I get list management down I will be over the first big hurdle of this project.

Corum

(Posted 2012) [#9]

Once mastered Scope and Objects' lifecycle concepts, You'll be Black Belt of Blitzmax. :-)
This modified code could make the TList Object management clearer.
Untested, as I haven't Blitzmax on the Office PC. :P

Global List:TList=New TList

Type TEnemy
	Field Health%
        Field ID:int
End Type

For e = 1 to 5
     EnemySpawn(e)
Next

For Local locEnemy:TEnemy = EachIn List
	Print locEnemy.Health
        Print locEnemy.ID
Next
End


Function EnemySpawn(e:int)
	Local Enemy1:TEnemy = New TEnemy
	Enemy1.Health=123
        Enemy1.ID = e
	List.AddLast Enemy1
End Function

Bee	(Posted 2012) [#10]

I actually found some more help digging through the posts and making better use of Methods and understanding how they related to the object's timeline/lifespan/existence/everything and how I can inherit it from the base as a "function".... it's all becoming muuuuuch clearer.

Corum, the enemy ID idea just might work better . I've done what I needed to, it's just very dirty , or at least I always feel like I'm taking the long way of doing it ;)

nitti

(Posted 2012) [#11]

I'd probably do it like this:


Function createEnemies:TList(amount:int)
    local enemyList:TList = new TList
    
    for local i:int = 0 until amount
        list.addLast(new TEnemy)
    next
    
    return enemyList
endFunction

like that you could call createEnemies(10) to create 10 enemies..
you'd get a list you can iterate over.

success, at one point things suddenly click and it'll be very easy I promise ;)
have fun

Last edited 2012