Wix Bind Substring or Split

I'm trying to get a Wix installer written that does some TypeLib registration.

I'm already pulling the FileVersion off a registered file elsewhere using

!(bind.FileVersion.#InteropDll)

but I want to do the same thing for the TypeLib, which only has separate MajorVersion and MinorVersion attributes. Ideally, I'd like to do

<TypeLib ... 
    MajorVersion="!(bind.FileVersion.InteropDll).Split('.')[0]" 
    MinorVersion="!(bind.FileVersion.InteropDll).Split('开发者_如何学JAVA.')[1]">

How can I accomplish this (or the like)? ...Or should I just not bother with all this and invoke regasm on the dll file at install time?

Thanks.

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The WiX toolset doesn't support doing that today. It's an interesting feature request. I would never call regasm during an install. It's way to hard to get rollback and patching and all that working correctly by shelling out to an external executable.