class RBS::Environment::MultiEntry

def initialize(name:)
  @name = name
  @decls = []
end

def insert(decl:, outer:)
  decls << D.new(decl: decl, outer: outer)
  @primary = nil
end

def primary
  raise "Not implemented"
end

def type_params
  primary.decl.type_params
end

def validate_type_params
  unless decls.empty?
    hd_decl, *tl_decls = decls
    raise unless hd_decl
    hd_params = hd_decl.decl.type_params
    hd_names = hd_params.params.map(&:name)
    tl_decls.each do |tl_decl|
      tl_params = tl_decl.decl.type_params
      unless hd_params.size == tl_params.size && hd_params == tl_params.rename_to(hd_names)
        raise GenericParameterMismatchError.new(name: name, decl: tl_decl.decl)
      end
    end
  end
end