Recommended coding convention for combining unix and windows code ?

[chmike via Digitalmars-d-learn]

Hello

I'm writing some code that I want to be portable across Posix and 
Windows.

What is the recommended code convention for such type of code ?

80% of the class implementation is the same for both OS.

Should I write the following and copy past the 80%

version( Windows ) {
     import core.sys.windows;
     class MyInfo {...}
} else version( Posix ) {
     import core.sys.posix;
     class MyInfo {...}
} else {
     static assert(false, "Unsupported platform");
}

or should I do it the C way with multiple embedded static if... ?

version( Windows ) {
     import core.sys.windows;
} else {  //Posix
     import core.sys.posix;
}

class MyInfo {
     ...
     static if(windows) {
     enum Value {...}
     } static else {  //Posix
     enum Value {...}
     }
     ...
}