Working on MT940 importer

[Best, Jan-Pascal van]

> Thanks a lot for working on this topic. However, there has 
> already been 
> some discussion about this topic in early July, see e.g. 
> http://article.gmane.org/gmane.comp.gnome.apps.gnucash.devel/9454
> Have you seen those emails, especially my remark about an 
> existing mt940 parser inside the OpenHBCI library?

Yes, I've read those. I looked at the OpenHBCI C API at
http://openhbci.sourceforge.net/doc/api/group__HBCI__APIg.html
but didn't find anything in there to parse MT940 files directly,
so I kind of gave up on that.

Not that I've looked further, the parser in swiftparser.cpp 
looks a fine piece of work (though the lex/yacc version looks 
cleaner ;-). Can I call the parser directly, without first creating 
an HBCI_API object? 

It doesn't seem like there is a C wrapper 
function available, at least not in core/swiftparser.h. Would it 
be possible to create one?

Alternatively, can I use C++ code in the importer 
module just to call this function? The code for reading from the file
could be in the gnucash module, just feeding strings to
SWIFTparser::readMT940 and then using trans_list_cb from 
gnc-hbci-gettrans.c to turn them into gnucash transactions.

Some more things: is the booking code (you call it "transaction key")
interpreted somewhere? Is there a possibility to allow unstructured
:86: fields (my bank has them)? Maybe the bank-specific parsing should
be done in openhbci instead of in gnucash by the way.

(I'll leave the discussion of interfacing with libmt940 for now, since the 
openhbci parser look quite nice and better maintained)

Jan-Pascal