Comment by zzzeek
5 years ago
this is the approach I'm familiar with, but back when I did it in Perl (yes Win32 perl with COM bindings) and Java (we wrote native Java plugins to do COM to Excel). all the important stuff is Excel VBA code that they spent years developing and can never replace, so any front end type of thing had to somehow get back to the Excel models.
We eventually did rewrite the Excel models in Java, released something, and then the whole project probably got cancelled or something, 9/11 happened a few years later and the whole building in which all this code was written had to be demolished.
I remember back in 2000 converting the windows line of business app team at $ISP (I was mostly on the provisioning automation side) over to using a COM component called JendaRex which wrapped the perl VM just to expose the regexp engine.
This basically came about after the Nth time they asked for regexp help and I had a trivial solution that didn't work in whatever native implementation they were using and I basically gave them a choice between JendaRex and "not having me debugging their regexps anymore".
They unanimously chose JendaRex and everybody ended up happier as a result.