Confusion over passing by reference vs passing by value

Confusion over passing by reference vs passing by value - Printable Version

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RE: Confusion over passing by reference vs passing by value - SMcNeill - 06-19-2022

As far as I know, BASIC doesn't allow one to set a whole array to some value all at once, which is what you're trying to do here:

satz3() = "SagNiemalsNie!"

You need an index of some sort to assign the value to, such as the below here:

Code: (Select All)
Dim satz3(10) As String

Print

satz3(0) = "SagNiemalsNie!"

Satztest3 satz3() '!! Damit hat der Compiler Probleme

Print "Wert des Feldes von satz3 nach der Subroutine: ", satz3(0)

End

Sub Satztest3 (feld() As String)

    feld(0) = feld(0) + "DonaldDuck"

End Sub

Note also that you can not pass arrays via parenthesis.

Satztest3 (satz3()) -- this is bugged and produces a c++ compile failure.

Satztest3 satz3() -- change it to this and it works perfectly fine.

RE: Confusion over passing by reference vs passing by value - Kernelpanic - 06-19-2022

Thanks SMcneill! It works now.

I constructed this "Satztest3 (satz3())" according to the manual for QBasic, but I misunderstood something.

RE: Confusion over passing by reference vs passing by value - DSMan195276 - 06-19-2022

I'm pretty sure this syntax is actually also a bug, identified in the previous QB64Team repository:

Code: (Select All)
feld() = feld() + "DonaldDuck"

What they said was that

feld()

was getting treated as

feld(0)

by mistake, which compiles but is obviously not what you wanted. Really this syntax should just produce a compiler error, it has no meaning.

This is the issue I was remembering, it should probably be added to the Phoenix Edition repo since it's still a bug: https://github.com/QB64Team/qb64/issues/216