isUpper package:unicode-data

Selects upper-case or title-case alphabetic Unicode characters (letters). Title case is used by a small number of letter ligatures like the single-character form of Lj. It matches characters with general category UppercaseLetter and TitlecaseLetter. See: isUpperCase for the full upper case predicate.

isUpper c == Data.Char.isUpper c

Returns True for upper-case characters. It uses the character property Uppercase. Note: it does not match title-cased letters. Those are matched using: generalCategory c == TitlecaseLetter. See: isUpper for the legacy predicate.