Hehe woops! and ye I think I did put the <TItem> there in the first place because I hoped to just be allowed to do array.subscribe( arrayChangedCallback ..) and it inferring the type but that didnt work. 


Should we just cancel this pull request and I clean things up based on comments and do a new pull request or whats best practise for changing things.    (a little new to pull requests, only done very simple stuff before).