# File lib/action_view/helpers/form_tag_helper.rb, line 345 def radio_button_tag(name, value, checked = false, options = {}) html_options = { "type" => "radio", "name" => name, "id" => "#{sanitize_to_id(name)}_#{sanitize_to_id(value)}", "value" => value }.update(options.stringify_keys) html_options["checked"] = "checked" if checked tag :input, html_options end