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Comment by ntoshev | Hacker News Reader

COM sort of works, on Windows, when when one or preferably both sides of the connecting components are made by Microsoft. You never see non-Microsoft code talking to non-Microsoft code from a different vendor via COM. This is not a successful component interface standard.

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Huh? ArcGIS is wholly extendable, and complete businesses are based on the Arc extension ecosystem, using COM. AutoCAD can (could?) be extended using COM. I've personally written extendable systems using COM. COM is a hugely successful component interface standard. Name any other standard with the same speed, flexibility and adoption.

Again, I'll agree that it's not trivial to implement a COM object. You need good understanding of C(++), the Windows API, threading, and some more things. There are tools to make it easier (e.g. to write a COM object in Visual Basic) but they generally don't make for robust components. In the hands of a competent, experienced developer, COM is a massively powerful tool.

It's not about COM.

COM is: "Unlike C++, COM provides a stable ABI that does not change between compiler releases. This makes COM interfaces attractive for object-oriented C++ libraries that are to be used by clients compiled using different compiler versions." http://en.wikipedia.org/wiki/Component_Object_Model

Others are talking about the compound document format OLE. And about DCOM (Distributed Component Object Model). Both OLE 1+2 and DCOM are not that great implementation wise, in retrospect. COM on the otherside is fine.

D-Bus is like DCOM, and has similar/other deficits, as do the competition: CORBA, RMI, XML-RPC, SOAP.

MDI and compound document format were an oversold concept, that failed. Today we have HTML5 with iframes.

I've written non-microsoft code that talks to non-microsoft code via COM. It was a painful experience, but you do in fact see it happen. I also know people who do this regularly, and seemingly fairly painlessly. I wouldn't call it a standard by any measure, more of an underdocumented and arcane mechanism.

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