MongoDB missing basic document(object) operators?

Thank you i was searching for that on JIRA also it would be nice we to have those,i upvoted
and i am watching it,but i don’t think i can create JIRA to ask for those.
if we have get we can do contains,and put using get and mergeobjects
(new value(we can do it even now) or updated).
I think remove is also needed,i don’t know a way to do it.


  $$mydoc   = one document
  $$mykey   = one key
  
  get("$$mydoc","$$mykey")   //we need this to be added
  contains?("$$mydoc","$$mykey")  //if we have get we can do it,with check if null/missing
  put("$$mydoc","$$mykey","randomValue")  //if we have get we can do it,with mergeObjects
  remove("$$mydoc","$$mykey")   //we need this to be added