Odd Behavoir Of Class Function

[Chrisn]

Hello. I am seeing really odd behavoir of class functions in DAQFacory.

I have a class MFC_Control defined in a startup routine with the following function in the definition (id and dig_Pot are local variables in the class):

//////////////////////////////////////Function to set pot-level for MFC//////////////////////////////

function set_Pot(potLevel)

private level

if(debug == 1)

? "Setting MFC"+id

? "potLevel to "+potLevel

endif

Pot_Pulse(id,127,0) // Pulse down 127 times to put pot in known state

Pot_Pulse(id,potLevel,1) // Pulse up potLevel times

dig_Pot = potLevel //update dig_Pot for later queary

if(dig_Pot < 0)

dig_Pot = 0

endif

if(dig_Pot > 127)

dig_Pot = 127

endif

endfunction

Then I initialize 4 of these as follows:

////////////////////////////////////////////////////////////////////////////////////////////////////////

/* CREATE MFC structrues with global access and initialize */

////////////////////////////////////////////////////////////////////////////////////////////////////////

global MFCS //Array of 4 objects MFC_Control

MFC_Init()

for(private.i = 0, i < 4, i++)

MFCS = new(MFC_Control)

MFCS.id = i+1

MFCS.set_Pot(0)

MFCS.turnOff()

MFCS.maxFlow = 2

endfor

MFCS[0].maxFlow = 5 //MFC1 will actually have a max flow of 5 L/min

MFCS[0].set_Pot(0)

MFCS[1].set_Pot(1)

MFCS[2].set_Pot(2)

MFCS[3].set_Pot(3)

This is all done in a startup script. The probelm is with the function set_Pot. When called in this sequence, its' input paramater is not passed (near as I can tell from debug lines). So when Pot_Pulse is called within this function to pulse the potentionmeter up, for MFCS[0] it works fine, but for MFCS[1] it gets pulsed up 2 times, MFCS[2] gets pulsed up 3 times ande MFCS[4] gets pulsed up 4 times.

Howerver, when I use this class function outside of this sequence (such as the command window or other sequences), they work just fine. Is there something I'm not understanding here?

[AzeoTech]

This is the one major bug in DAQFactory OOP and why OOP has remained undocumented. Truthfully, its not really a bug as much as a limitation in the original expression parser. Anyhow, the issue it that you can't have more than one () or [] when referencing a symbol or function. So: MFCS.set_Pot(0) is invalid because you have both and (0). The workaround is pretty simple, though understandably annoying: assign the arrayed object to a private variable, then reference that:

private newMFCS = new(MFC_Control)

MFCS = newMFCS

newMFCS.id = i+1

newMFCS.set_Pot(0)

etc...

and:

for (private i = 0, i < numrows(MFCS), i++)

private tMFCS = MFCS

tMFCS.set_Pot(i)

endfor

[Chrisn]

Ah, I see.

I already made a seperate work around, but this is good to keep in mind. Thanks.