module Mongoid::Contextual::Aggregable::None
Contains behavior for aggregating values in null context.
Public Instance Methods
Get all the aggregate values for the provided field in null context. Provided for interface consistency with Aggregable::Mongo
.
@param [ String | Symbol ] _field The field name.
@return [ Hash ] A Hash with count, sum of 0 and max, min, avg of nil.
# File lib/mongoid/contextual/aggregable/none.rb, line 18 def aggregates(_field) Aggregable::EMPTY_RESULT.dup end
Always returns nil.
@example Get the avg of null context.
@param [ Symbol ] _field The field to avg.
@return [ nil ] Always nil.
# File lib/mongoid/contextual/aggregable/none.rb, line 40 def avg(_field) nil end
Always returns nil.
@example Get the max of null context.
@param [ Symbol ] _field The field to max.
@return [ nil ] Always nil.
Always returns nil.
@example Get the min of null context.
@param [ Symbol ] _field The field to min.
@return [ nil ] Always nil.
# File lib/mongoid/contextual/aggregable/none.rb, line 51 def min(_field = nil) nil end
Always returns zero.
@example Get the sum of null context.
@param [ Symbol ] _field The field to sum.
@return [ Integer ] Always zero.
# File lib/mongoid/contextual/aggregable/none.rb, line 29 def sum(_field = nil) 0 end