• active_support/core_ext/string/inflections
• active_support/core_ext/string/conversions
• active_support/core_ext/string/access
• active_support/core_ext/string/starts_ends_with
• active_support/core_ext/string/iterators
• active_support/core_ext/string/unicode
• active_support/core_ext/string/xchar
• active_support/core_ext/string/filters