< cpp | locale | ctype char
Defined in header
bool is( mask m, char c ) const;
const char* is( const char* low, const char* high, mask* vec ) const;
1) Checks if the character c is classified by the mask m according to the classification table returned by the member function table(). Effectively calculates table()[(unsigned char)c] & m.
2) For every character in the character array
[low, high), reads its full classification mask from the classification table returned by the member function table() (that is, evaluates table()[(unsigned char)*p] and stores it in the corresponding element of the array pointed to by vec.
If (unsigned char)c >= std::ctype<char>::table_size, then an implementation-defined value is substituted instead of table()[(unsigned char)c], possibly different for different values of c.
|c||-||character to classify|
|m||-||mask to use for classifying a single character|
|low||-||pointer to the first character in an array of characters to classify|
|high||-||one past the end pointer for the array of characters to classify|
|vec||-||pointer to the first element of the array of masks to fill|
 Return value
1) true if c is classified by m in table(), false otherwise
Unlike the primary template std::ctype, this specialization does not perform a virtual function call when classifying characters. To customize the behavior, a derived class may provide a non-default classification table to the base class constructor.
|This section is incomplete|
Reason: no example
 Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
|DR||Applied to||Behavior as published||Correct behavior|
|LWG 28||C++98|| overload (2) copied the values from vec into table(),
which is the reverse of the intended behavior
 See also
| classifies a character or a character sequence |
(virtual protected member function of