public member type
std::ctype::mask
<locale>
Character category bitmask type
This member type is inherited from
ctype_base.
It is a bitmask type used as parameter for member functions
is,
scan_is and
scan_not, and may take any bitwise combination of the following
enum values:
| value | Characteristics |
|---|
| space | White-space character |
| print | Printable character |
| cntrl | Control character |
| upper | Uppercase letter |
| lower | Lowercase letter |
| alpha | Alphabetic letter |
| digit | Decimal digit |
| punct | Punctuation mark |
| xdigit | Hexadecimal character |
These categories are based on those defined in the C library header
<cctype>. See the reference for
cctype for the classification in these categories of characters of type
char.