how to use $push: '$$ROOT'

[Ram Odedara]

hi 

i am using reactivemongo 12.6 and i want to push whole result in a variable any body know how to use this group query in reactivemongo 

{"$group":{

    "_id":null,

     "count":{$sum:1},

    "result":{$push: '$$ROOT'}

    }}

[Cédric Chantepie]

Group is an aggregation stage, whose usage can be seen in the documentation: http://reactivemongo.org/releases/0.12/documentation/advanced-topics/aggregation.html#group