map -package:charset -package:basement -package:foldl -package:invertible -package:integration -package:base -package:bytestring -package:filepath -is:exact package:case-insensitive -is:exact

map :: FoldCase s2 => (s1 -> s2) -> CI s1 -> CI s2
case-insensitive Data.CaseInsensitive
Transform the original string-like value but keep it case insensitive.