Name an association key based on value in collection

Question

[copied from GT FB group]

Is there a way to name an association key based on a specific value from a collection?

Here's what I got so far: https://www.guidedtrack.com/programs/o8ry2ho/preview

On line 21: it says it couldn't detect it as a command

 

Answer 1

https://www.guidedtrack.com/programs/8925/edit