--- !ruby/object:RI::MethodDescription 
aliases: 
- !ruby/object:RI::AliasName 
  name: member?
- !ruby/object:RI::AliasName 
  name: include?
- !ruby/object:RI::AliasName 
  name: has_key?
- !ruby/object:RI::AliasName 
  name: key?
block_params: 
comment: 
- !ruby/struct:SM::Flow::P 
  body: Returns true if the message has a field named 'name'.
full_name: RMail::Header#field?
is_singleton: false
name: field?
params: (name)
visibility: public
