I have technical issue I'm trying to overcome as it applies to exporting sharepoint lists based on Infopath forms to Excel to create reports as it applies to Repeating Tables embeded in Repeating Sections. Wow thats a mouthful!
Ok lets see if I can break this down a bit.
What Im trying to acomplish
I have an infopath form with repeating tables (repeating fields) that are being pushed out to a sharepoint forms library list using the "merge" function. This displays data in a nice neat format in sharepoint stacking each field added to from a repeating table field. We now have a new requirement where we export our sharepoint lists based on this form library to excel for reporting purposes. Naturally since its a merged field when exporting to excel the field is merged in excel as well. The goal is to split these fields up into seperate fields in excel. The simplest way I can think of doing this is to add a delimeter (a comma for example) into the field during the creation of the form so that it appears in the sharepoint list and hence is exported with the delimeter to excel. This would allow us using excel (replace function) to split up the cells into seperate fields for various calculations, lookups etc..
How to accomplish this in Infopath
I know that the function I should be using is the Eval function (I have read a few posts on the topics here) but I think my situation is a bit different then the examples and Im having trouble structuring it. I created an example with screen shows here just for clarification.

In the first box I select from a list of items, adding more items by clicking Insert Item when in preview mode.
When this form is published I use the "Merge" function.
When its saved to the form the items display as followed

The merged field appears stacked, but no delimeters naturally. When you export this to excel it looks the same in the cells (merged fields).
What I need to do is seperate these items by a delimeter.
The question is how to best acomplish this. first and foremost is there a built in function in Infopath (an option in the advanced menu or otherwise) that can acomplish this without any special functions or usage of code. if not, assuming we are using the Eval function, how exactly should it be scripted.
I suspected that it should be pushed out to a temporary text field and use the concat function or a combination of eval and concat but everything I have tried has prompted errors in the formula. I suspect Im on the right track but havent been able to get it quite right.
Any help would be appriciate it, its more important that I understand the "hows" of it then just fixing the problem so any detail would be in particular helpful.
Thanks in advance for any help
Just FYI: this is the Eval im trying to get working, I believe its roughly correct but its complaining that Im missing an apperand, but I really can't see where
xdMath:Eval(xdMath:Eval(my:group1/my:Delimiter/my:group3/my:group4/my:ProductCapture,'concat(my:group1/my:Delimiter/my:group3/my:group4/my:ProductCapture,",")