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.....................................................................................................................................--- !ruby/object:RI::MethodDescription 
aliases: []

block_params: 
comment: 
- !ruby/struct:SM::Flow::P 
  body: Adds the given object to the set and returns self. If the object is already in the set, returns nil.
full_name: Set#add?
is_singleton: false
name: add?
params: (o)
visibility: public