Passing Variable Names with Values to a paramarray

[cafeenman]

I'm starting to have a lot of Flags in my application and it's hard to keep track of the status of them all.

Sometimes I want to temporarily change a flag if it's a certain value and then restore the value.

The simple way is.

Private ASub As Sub
Dim flg As Boolean

flg = Flags(0)

Flags(0)=False

' do sub stuff

Flags(0) = flg

Of course the problem with that is when you have sixteen flags and your whole sub turns into turning flags on and off and five lines of code that's actually doing anything.

So what I tried was this which failed immediately:

(and now looking back at it I can see that I was just doing a stupid bugassert and not passing a variable name at all. I know better. probably...)

' Flags in whatever modules.  I like to group them all into one.

Private fAllowFlickering As Boolean
Private fShowDieRolls As Boolean

' Both Properties below have an associated Property Let of course.

Public Property Get AllowFlickering As Boolean

AllowFlickering = fAllowFlickering 

End Property
Public Property Get ShowDieRolls As Boolean

ShowDieRolls = fShowDieRolls

End Property

Private Sub SetRestoreFlags(ParamArray Variables())
Dim n As Long

For n = LBound(Variables) To UBound(Variables)

  MsgBox Variables(n)

Next n

End Sub

Private Sub Form_Load()

SetRestoreFlags AllowFlickering = False, ShowDieRolls = True

End Sub

SetRestoreFlags would actually be a class module that was initiated with whatever I want the flags to be.

Any time a Flag status is sent to the Class, it would save the current value in a collection or array.

This would mean that the Flags sent must be Public or Friend in scope.

On Class Terminate it would restore all flags to whatever value they were.

Example case:

You can turn Definitions on or off (Definitions of words used in the app). They appear in an auxilliary window.

So In the DisplayDefinition sub, it would check this flag and kick out if disabled or display the definition if enabled.

But maybe there's a definition I want the user to see and I want to override the setting.

So what I'm trying to achieve is doing this without having to send every possible flag.

I mean I still have to type out all the flags but it's one line of code plus the class declaration.

But that's still better than however many lines of code at the beginning and end of any sub it applies to.

Not to mention, much easier debugging because it's all in one place.

And I want to send the flags in any quantity and in any order.

If it recognizes the flag-property variable then it knows what to do with it.

I know there are a lot of ways to do this and I've been doing all of them.

But I'm looking for something more automated so I can just send off a list of flags and the status I want them to be temporarily and when it's done the class goes out of scope and the sub exits with flags set as they were when the sub was entered.

[cafeenman]

Here's an example of one thing I'm doing now.

The entire app is Random stuff happening. Think software version of a Rube Goldberg machine.

But it's controlled randomness.

Some things do not want to be disturbed.

In this case, "Disturbed" means text from one thing showing up in the middle of something else that was already going on and then the original thing continues.

Some subs don't care if they're disturbed.

But they're not allowed to disturb other subs.

Example:

Sub CanBeDisturbedButNotDisturbOthers

If DoNotDisturb Then Exit Sub ' Public property

' Do stuff.

End Sub

Sub CanNotBeDisturbedOrDisturbOthers
Dim m_DoNotDisturb as cDoNotDisturb

If DoNotDisturb Then Exit Sub

Set m_DoNotDisturb = New cDoNotDisturb ' On Class Initialize sets DoNotDisturb = True
                                       ' On Terminate, sets DoNotDisturb = False

' Do stuff.

' m_DoNotDisturb goes out of scope upon sub exit.

End Sub

[cafeenman]

OK, I think I might have just figured it out.

And that is to make a Flag class and send that to a collection class instead of sending property names.

Not sure how complicated that will be or how long the calls will be because I just now thought of it and that's as far as I've gotten.

' some thinking passes....

OK, I think the way it needs to work is to still pass all the flags individually.

So all this really saves me is the resetting them at the end of the sub.

But the beginning of the sub is just as messy.

So what gets sent to the collection class is this.

Sub DoThing
dim m_FlagCollector as New cFlagCollector

m_FlagCollector.Add AllowFlickering, False '  It gets the current flag and temporary value you're setting.
m_FlagCollector.Add ShowDefinitions, True  '  Then it saves the original value internally before setting the new value.

' Do stuff.

End Sub

Not sure that's really worth the effort but maybe.

Because I really want to turn this into one line of code.

This could work but I don't like it.

It would be cool if there were a way to send two paramarrays. But I can't.

I keep thinking a Pipe character | could have been used to tell the compiler where
a parameter array ends so that anything else could come after it including another paramarray.

[cafeenman]

Actually, now that I think about it some more, this whole idea is really stupid.

Is there a way to delete this thread?

The problem now is that the Sub that creates the FlagCollector still needs to know what the status of all those flags is to know what to do.

One flag might want you to not do the sub if it's set.

Another might want the sub to enter text into a different textbox.

Another might be deciding what sound to play.

So regardless I still need to check all those status after the collector gets everything and I probably end up with even more lines of code.

sorry to bother you all.

This was a dumb idea.

But I still have the same problem that I don't know if I should even do anything about it.

It's working but getting more unwieldy as the app grows.

[Zvoni]

So, you have 16 Flags...... True or False..... 1 or 0

Funny, how an Integer-Type also has 16 Bits, which can be 1 or 0......

[DrBobby]

How about something like this?

Const FLAG_1 = &H1   ' 00000001
Const FLAG_2 = &H2   ' 00000010
Const FLAG_3 = &H4   ' 00000100
Const FLAG_4 = &H8   ' 00001000

Public Function SetFlag(ByVal value As Long, ByVal flag As Long) As Long
    ' Function to set a flag
    SetFlag = value Or flag
End Function

Public Function ClearFlag(ByVal value As Long, ByVal flag As Long) As Long
    ' Function to clear a flag
    ClearFlag = value And Not flag
End Function

Public Function IsFlagSet(ByVal value As Long, ByVal flag As Long) As Boolean
    ' Function to check if a flag is set
    IsFlagSet = (value And flag) <> 0
End Function

Private Sub Form_Load()
    Dim value As Long
    value = 0

    ' Set some flags
    value = SetFlag(value, FLAG_1)
    value = SetFlag(value, FLAG_3)

    ' Check flags
    Debug.Print "FLAG_1 is set: " & IsFlagSet(value, FLAG_1)
    Debug.Print "FLAG_2 is set: " & IsFlagSet(value, FLAG_2)
    Debug.Print "FLAG_3 is set: " & IsFlagSet(value, FLAG_3)

    ' Clear a flag
    value = ClearFlag(value, FLAG_1)
    Debug.Print "FLAG_1 is set after clearing: " & IsFlagSet(value, FLAG_1)
End Sub

[alivale]

I didn't understand the essence of the problem, but this immediately came to my mind.

Private Sub TestParamArray()
    Dim param1, sName$
    
    param1 = 1: sName = "param1"
    GetMem4 ByVal VarPtr(sName), ByVal VarPtr(param1) + 2
    
    SomeSub param1
End Sub
Private Sub SomeSub(ParamArray params())
    Dim i&, sTmp$
    For i = 0 To UBound(params)
        GetMem4 ByVal VarPtr(params(i)) + 2, ByVal VarPtr(sTmp)
        Debug.Print sTmp & ": "; params(i)
    Next
    GetMem4 0&, ByVal VarPtr(sTmp)
End Sub