ctype_base ctype<char>
A specialization of the ctype facet.
| Member Functions | |
| classic_table() do_tolower() do_toupper() is() narrow() scan_is() |
scan_not() table() tolower() toupper() widen() |
#include <locale> class ctype<char>;
This specialization of the ctype<charT> template includes inline versions of ctype's member functions. The facet has the same public interface and uses the same set of masks as the ctype template.
template <>
class ctype<char> : public locale::facet, public ctype_base {
public:
typedef char char_type;
explicit ctype(const mask* = 0, bool = false,
size_t = 0);
bool is(mask, char) const;
const char* is(const char*,
const char*, mask*) const;
const char* scan_is(mask,
const char*,
const char*) const;
const char* scan_not(mask,
const char*,
const char*) const;
char toupper(char) const;
const char* toupper(char*, const char*) const;
char tolower(char) const;
const char* tolower(char*, const char*) const;
char widen(char) const;
const char* widen(const char*,
const char*, char*) const;
char narrow(char, char) const;
const char* narrow(const char*, const char*,
char, char*) const;
static locale::id id;
static const size_t table_size = 256;
protected:
const mask* table() const throw();
static const mask* classic_table() throw();
~ctype(); // virtual
virtual char do_toupper(char) const;
virtual const char* do_toupper(char*,
const char*) const;
virtual char do_tolower(char) const;
virtual const char* do_tolower(char*,
const char*) const;
};
char_type
Type of character the facet is instantiated on.
explicit ctype(const mask* tbl = 0, bool del = false,
size_t refs = 0)
Construct a ctype facet. The three parameters set up the following conditions:
The tbl argument must be either 0 or an array of at least table_size elements. If tbl is non-zero, then the supplied table is used for character classification.
If tbl is non zero, and del is true, then the tbl array is deleted by the destructor, so the calling program need not concern itself with the lifetime of the table.
If the refs argument is 0, then destruction of the object itself is delegated to the locale, or locales, containing it. This allows the user to ignore lifetime management issues. On the other hand, if refs is 1, then the object must be explicitly deleted; the locale does not do so.
~ctype(); // virtual and protected
Destroy the facet. If the constructor was called with a non-zero tbl argument and a true del argument, then the array supplied by the tbl argument is deleted.
The public members of the ctype<char> facet specialization do not all serve the same purpose as the functions in the template. In many cases these functions implement functionality, rather than just forwarding a call to a protected implementation function.
static const mask* classic_table() throw();
Returns a pointer to a table_size character array that represents the classifications of characters in the "C" locale.
bool is(mask m, char c) const;
Determines if the character c has the classification indicated by the mask m. Returns table()[(unsigned char)c] and m.
const char* is(const char* low, const char* high, mask* vec) const;
Fills vec with every mask from ctype_base that applies to the range of characters indicated by [low,high). See ctype_base for a description of the masks. For instance, after the following call, the first five elements of v would contain: alpha|lower|print|xdigit|graph}:
char a[] = "abcde"; ctype_base::mask v[12]; ctype<char>().do_is(a,a+5,v);
Returns high.
char narrow(char c, char dfault) const;
Returns c.
const char*
narrow(const char* low, const char*, char dfault,
char* to) const;
Performs ::memcpy(to,low,high-low). Returns high.
const char* scan_is(mask m, const char*, const char* high) const;
Finds the first character in the range [low,high) that matches the classification indicated by the mask m. The classification is matched by checking for table()[(unsigned char) p] & m, where p is in the range [low,high). Returns the first p that matches, or high if none do.
const char* scan_not(mask m, const char* low, const char* high) const;
Finds the first character in the range [low,high) that does not match the classification indicated by the mask m. The classification is matched by checking for !(table()[(unsigned char) p] & m), where p is in the range [low,high). Returns the first p that matches, or high if none do.
const mask* table() const throw();
If the tbl argument that was passed to the constructor was non-zero, then this function returns that argument. Otherwise it returns classic_table().
char tolower(char c) const; const char* tolower(char* low, const char* high) const;
Returns do_tolower(c) or do_tolower(low,high).
char toupper(char) const; const char* toupper(char* low, const char* high) const;
Returns do_toupper(c) or do_toupper(low,high).
char widen(char c) const;
Returns c.
const char* widen(const char* low, const char* high, char* to) const;
Performs ::memcpy(to,low,high-low). Returns high.
static locale::id id;
Unique identifier for this type of facet.
virtual char do_tolower(char) const;
Returns the lower case representation of c, if such exists. Otherwise returns c.
virtual const char* do_tolower(char* low, const char* high) const;
Converts each character in the range [low,high) to its lower case representation, if such exists. If a lower case representation does not exist, then the character is not changed. Returns high.
virtual char do_toupper(char c) const;
Returns the upper case representation of c, if such exists. Otherwise returns c.
virtual const char* do_toupper(char* low, const char* high) const;
Converts each character in the range [low,high) to its upper case representation, if such exists. If an upper case representation does not exist, then the character is not changed. Returns high.
locale, facets, collate, ctype<char>, ctype_byname