[category.ctype.general]

# 28 Text processing library [[text]](./#text)

## 28.3 Localization library [[localization]](localization#category.ctype.general)

### 28.3.4 Standard locale categories [[locale.categories]](locale.categories#category.ctype.general)

#### 28.3.4.2 The ctype category [[category.ctype]](category.ctype#general)

#### 28.3.4.2.1 General [category.ctype.general]

[ð](#lib:ctype_base)

namespace std {class ctype_base {public:using mask = *see below*; // numeric values are for exposition only.static constexpr mask space = 1 << 0; static constexpr mask print = 1 << 1; static constexpr mask cntrl = 1 << 2; static constexpr mask upper = 1 << 3; static constexpr mask lower = 1 << 4; static constexpr mask alpha = 1 << 5; static constexpr mask digit = 1 << 6; static constexpr mask punct = 1 << 7; static constexpr mask xdigit = 1 << 8; static constexpr mask blank = 1 << 9; static constexpr mask alnum = alpha | digit; static constexpr mask graph = alnum | punct; };}

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/text.tex#L1343)

The type mask is a bitmask type ([[bitmask.types]](bitmask.types "16.3.3.3.3 Bitmask types"))[.](#1.sentence-1)
