#Null a procedure parameter?

[wayne-c]

I have the following procedure:

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Procedure Test(Text$, Map Args$())
...
EndProcedure

Sometimes I do not have the Map available, thus I would like to call the function as follows:

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Test("Hello World", #Null)

This is not possible and results in a compile error: "Bad parameter type: a map is expected."

Is there any workaround or best practice to handle such a case?

This is possible however it seems like a bad hack to me:

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Global NewMap DummyMap$()

Procedure Test(Text$, Map Args$())
...
EndProcedure

Test("Hello World", DummyMap$())

When working with the dummy map, I cannot find out inside the procedure if there was a real map or the dummy map passed (to be able to skip the functionality whenever the dummy map is passed)

Any ideas folks?

[RSBasic]

Maybe with this code: viewtopic.php?p=531868#p531868

[wayne-c]

Maybe with this code: viewtopic.php?p=531868#p531868

That would mean to wrap all parameters inside a wrapper structure, right? Well I hope there is an easier approach out there...

[skywalk]

If your Procedure expects a Map(), then check for the Map() before calling the Procedure.
Or create a structure that holds the Map() and set a structure parameter like \useMap = 0|1.
Then pass the structure to the Procedure.

[Demivec]

You can simply test for an empty map ,

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If MapSize(Args$()) = 0
     ;no arguements
EndIf

[wayne-c]

You can simply test for an empty map ,

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If MapSize(Args$()) = 0
     ;no arguements
EndIf

Unfortunately not; my function receives an empty map and fills it inside. But if the caller does not want the map to be filled, it just uses power/memory for nothing.

But passing a dummy map and an additional parameter useMap=1|0 will do the trick; however to declare and passing an unused map is imho a bit hacky. #Null - as e.g. in Objective-C - would just make more sense here.