Shipen, with money behind MS & Adobe,why would they not build suitable filters for their products?
TXT only needed a simple filter but even text files come in different flavours.
MMAP is XML-based anyhow.

The MS Office suite is both deliverable and editable. The XAR format is editable and proprietary and is not published. That's the difference.
The WIX format does what you want.

You have yet to present your own specific need.
You have a gazillion XAR files and you always mispell theit/there/thier.
A Windows filter finds 7 files. You don't know where in the files...

Acorn