shiny/srcjs/output_binding_text.js

  var textOutputBinding = new OutputBinding();
  $.extend(textOutputBinding, {
    find: function(scope) {
      return $(scope).find('.shiny-text-output');
    },
    renderValue: function(el, data) {
      $(el).text(data);
    }
  });
  outputBindings.register(textOutputBinding, 'shiny.textOutput');