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From: Lawson.English@p88.f15.n300.z1.fidonet.org (Lawson English)
Newsgroups: comp.sys.mac.programmer
Subject: MacApp and DAs (was: Re: Local/AppleTalk Connectivity in MacApp)
Message-ID: <34332.278959EE@stjhmc.fidonet.org>
Date: 6 Jan 91 17:15:45 GMT
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lanett mark writes in a message to All

LM>  The point here is that C++ objects dynamically allocate memory, 
LM> which makes them unsuitable for this kind of program (I'm not 
LM> sure about Object Pascal). Also, since they pass the hidden this/self 
LM> pointer, you cannot pass a member function to the toolbox--they 
LM> have that extra parameter. 

You CAN pass a member function to the Toolbox, albeit indirectly...

However you create "globals" for your DA, simply create a "gFilterFuncPtr" that
is accessed by your filter function, thusly:

void MyFilterFunction(void);
{
     gFilterFuncPtr->Filter();    { whatever the syntax is for C++ (I forget)
}
}


Lawson
 

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