How to stop Concat() function from ordering values i select?

[Thathayoyo]

Hello,

I have a table :

[Table]:

LOAD * INLINE [Dim,DimID

NameA, A

NameB, B

NameC, C

NameD, D];

This Table is put in a filter and so i can select values of [Dim] inside the filter. I want to know what is the first value i select so I use this expression: SubField(Concat([DimID], '|',', '),'|',1). 

For example if I select in first 'NameB' and then second 'NameA' in the filter, i want my expression return B. The problem is that Concat() all time order value so i obtain A as the result. How can i do to stop Concat() to order values?

Thanks.

[Kushal_Chawda]

@Thathayoyo  try below

=Only({<Dim = {"$(=trim(SubField(GetFieldSelections(Dim),',',-1)))"}>}DimID)

[Thathayoyo]

Hello thank but GetFieldSelections() also order automatically values so it does not works.

[marcus_sommer · Accepted solution]

It's each time a new calculation against the current selection state and therefore concat() must re-order the included values.

To track the order in which dimensionn-values are selected you may use the appropriate set analysis feature within the identifier of {$1} respectively {$_1} to query the previous/following selection state - and then querying the n states against each other.

But if your scenario isn't a rather simple case it may become ugly with a lot of (nested) if-loops.