def extrai_blocos_yaml(conteudo)
      result = {}
      Open3.popen3("pandoc -t json") {|stdin, stdout, stderr, wait_thr|
        pid = wait_thr.pid # pid of the started process.
        stdin.write conteudo
        stdin.close
        meta = JSON.parse(stdout.read)[0]['unMeta']
        meta.each do |k,v|
          result[k]=converte_valor_da_arvore_pandoc(v)
        end
      }
      result
    end
def extrai_blocos_yaml(conteudo)
      result = {}
      Open3.popen3("pandoc -t json") {|stdin, stdout, stderr, wait_thr|
        pid = wait_thr.pid # pid of the started process.
        stdin.write conteudo
        stdin.close
        meta = JSON.parse(stdout.read)[0]['unMeta']
        meta.each do |k,v|
          result[k]=converte_valor_da_arvore_pandoc(v)
        end
      }
      result
    end
Returna um hash contendo os conteúdos lidos dos blocos yaml.