• cgi
• erb
• active_support/core_ext/string/output_safety
• active_support/core_ext/array/extract_options
• active_support/core_ext/array/wrap
• action_view/helpers/text_helper

• 模組 ActionView
• 模組 ActionView::Helpers
• 模組 ActionView::Helpers::FormOptionsHelper
• 模組 ActionView::Helpers::Tags
• 類別 ActionView::Helpers::FormBuilder