Hi Peter,

I understand that you want to check if a list contains an certain object. 

For that you can use the activity list operation with option Contains: https://docs.mendix.com/refguide7/list-operation

When it returns true you know the object already is in the list.

Hope that helps.

thanks for the quick reaction.
I indeed forgot to include what I did, mostly because what I did wasnt really that substancial.
I am rather new to the XPath's and expressions, I had a brief look into the contains but can't seem to figure it out.
What I tried to do was make a list.

from this I tried searching with an expression in a 'exclusive split'

the expression I used was: $Order_RegelList.contains('$Product/artikelnummer')
I have found different ways of how people use contains, the idea I had here was to look through the list.
And then see if $Product/artikelnummer was in it (%Product is the product that I pass into the microflow, with the intent of placing it in my order. artikelnummer is the artikel number used to identity the product.)

Any thoughs on what I missed/did wrong?

btw, with this expression I get the error 'missing EOF at '.'' which reffers to the period before contains.

thanks in advance for looking at it and trying to lend me a hand

Here's an update of what I did, I tried to implement a loop that iterates over all the Order_Regels in Order.
But for some reason it never finds a match, I have the linguering feeling that I have missed something obvious.
Although I've searched for a bit, I cant seem to find an example I understand of how to do a microflow in a loop. At least not one that explains what error I made in mine, hope someone can point out my mistake.

I tried to include all relevant information, hope its enough.

here is the second part of my flow, now with inclusion of a breakpoint in the loop.

here by also the iterator loop, and the part of my doman model I though would be relevant.