wctypedigit
Wctypedigit is a term used in some wide-character processing contexts to denote the digit classification for wide characters. It refers to the set of characters that represent decimal digits, including ASCII digits as well as digits from other scripts when Unicode or locale data are in use. In this sense, wctypedigit is part of a broader scheme for classifying characters by type rather than by their visual shape alone.
In practice, wctypedigit can appear as either a predicate function or as a type mask within a
Unicode and locale considerations are central to wctypedigit. In Unicode terms, the digit property covers decimal
See also: iswdigit, wctype, and locale-based character classification. Note that wctypedigit is a descriptive concept used