Creating a unique collection in flow

this is a very short post, that shows one small thing that can be very useful - creating a collection of unique elements in visual workflow

there are now quite a few operators on collections in flow, but none of them are ‘remove duplicates’ or ‘add if new’ or anything like that.

i found a way to do this that requires only a single assignment element - no extra loops or decisions to evaluate if the collection already contains the element required.

This assignment would run within a loop, and would build the collection. The new transform element can build the collection in one step, but it would still need to be deduped.

step 1 : remove all instances of (X)
step 2: add (X)

this ensures that your collection will only contain one copy of the element.

maybe there is an easier way, but this works!