Psych::TreeBuilder.new

# File tmp/rubies/ruby-4.0.0/ext/psych/lib/psych/tree_builder.rb, line 22
def initialize
  @stack = []
  @last  = nil
  @root  = nil

  @start_line   = nil
  @start_column = nil
  @end_line     = nil
  @end_column   = nil
end