std::ctype< char > Class Template Reference
Locales
Inheritance diagram for std::ctype< char >:
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## Public Types

typedef const int * | __to_type
typedef char | char_type
typedef unsigned short | mask

## Public Member Functions

| ctype (const mask *__table=0, bool __del=false, size_t __refs=0)
| ctype (__c_locale __cloc, const mask *__table=0, bool __del=false, size_t __refs=0)
bool | is (mask __m, char __c) const
const char * | is (const char *__lo, const char *__hi, mask *__vec) const
char | narrow (char_type __c, char __dfault) const
const char_type * | narrow (const char_type *__lo, const char_type *__hi, char __dfault, char *__to) const
const char * | scan_is (mask __m, const char *__lo, const char *__hi) const
const char * | scan_not (mask __m, const char *__lo, const char *__hi) const
const mask * | table () const throw ()
char_type | tolower (char_type __c) const
const char_type * | tolower (char_type *__lo, const char_type *__hi) const
char_type | toupper (char_type __c) const
const char_type * | toupper (char_type *__lo, const char_type *__hi) const
char_type | widen (char __c) const
const char * | widen (const char *__lo, const char *__hi, char_type *__to) const

## Static Public Member Functions

static const mask * | classic_table () throw ()

## Static Public Attributes

static const mask | alnum
static const mask | alpha
static const mask | blank
static const mask | cntrl
static const mask | digit
static const mask | graph
static locale::id | id
static const mask | lower
static const mask | print
static const mask | punct
static const mask | space
static const size_t | table_size
static const mask | upper
static const mask | xdigit

## Protected Member Functions

virtual | ~ctype ()
virtual char | do_narrow (char_type __c, char __dfault __attribute__((__unused__))) const
virtual const char_type * | do_narrow (const char_type *__lo, const char_type *__hi, char __dfault __attribute__((__unused__)), char *__to) const
virtual char_type | do_tolower (char_type __c) const
virtual const char_type * | do_tolower (char_type *__lo, const char_type *__hi) const
virtual char_type | do_toupper (char_type __c) const
virtual const char_type * | do_toupper (char_type *__lo, const char_type *__hi) const
virtual char_type | do_widen (char __c) const
virtual const char * | do_widen (const char *__lo, const char *__hi, char_type *__to) const

## Static Protected Member Functions

static __c_locale | _S_clone_c_locale (__c_locale &__cloc) throw ()
static void | _S_create_c_locale (__c_locale &__cloc, const char *__s, __c_locale __old=0)
static void | _S_destroy_c_locale (__c_locale &__cloc)
static __c_locale | _S_get_c_locale ()
static const char * | _S_get_c_name () throw ()
static __c_locale | _S_lc_ctype_c_locale (__c_locale __cloc, const char *__s)

## Protected Attributes

__c_locale | _M_c_locale_ctype
bool | _M_del
char | _M_narrow [1+static_cast< unsigned char >(-1)]
char | _M_narrow_ok
const mask * | _M_table
__to_type | _M_tolower
__to_type | _M_toupper
char | _M_widen [1+static_cast< unsigned char >(-1)]
char | _M_widen_ok

## Detailed Description

### template<>
class std::ctype< char >

The ctype<char> specialization.

This class defines classification and conversion functions for the char type. It gets used by char streams for many I/O operations. The char specialization provides a number of optimizations as well.

Definition at line 681 of file locale_facets.h.

## Member Typedef Documentation

## char_type

typedef char std::ctype< char >::char_type

Typedef for the template parameter char.

Definition at line 686 of file locale_facets.h.

## Constructor & Destructor Documentation

## ctype() [1/2]

std::ctype< char >::ctype | ( | const mask * | __table = `0`,
|  | bool | __del = `false`,
|  | size_t | __refs = `0`
| ) |  |

explicit

Constructor performs initialization.

This is the constructor provided by the standard.

Parameters

  __table | If non-zero, table is used as the per-char mask. Else classic_table() is used.
  __del | If true, passes ownership of table to this facet.
  __refs | Passed to the base facet class.

## ctype() [2/2]

std::ctype< char >::ctype | ( | __c_locale | __cloc,
|  | const mask * | __table = `0`,
|  | bool | __del = `false`,
|  | size_t | __refs = `0`
| ) |  |

explicit

Constructor performs static initialization.

This constructor is used to construct the initial C locale facet.

Parameters

  __cloc | Handle to C locale data.
  __table | If non-zero, table is used as the per-char mask.
  __del | If true, passes ownership of table to this facet.
  __refs | Passed to the base facet class.

## ~ctype()

virtual std::ctype< char >::~ctype | ( |  | ) |

protected virtual

Destructor.

This function deletes table() if del was true in the constructor.

## Member Function Documentation

## classic_table()

static const mask* std::ctype< char >::classic_table | ( |  | ) |
throw | ( |
| ) |  |

static

Returns a pointer to the C locale mask table.

## do_narrow() [1/2]

virtual char std::ctype< char >::do_narrow | ( | char_type | __c,
|  | char __dfault | __attribute__(__unused__)
| ) |  | const

inline protected virtual

Narrow char.

This virtual function converts the char to char using the simplest reasonable transformation. If the conversion fails, dfault is returned instead. For an underived ctype<char> facet, c will be returned unchanged.

do_narrow() is a hook for a derived facet to change the behavior of narrowing. do_narrow() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __c | The char to convert.
  __dfault | Char to return if conversion fails.

Returns
  The converted char.

Definition at line 1131 of file locale_facets.h.

## do_narrow() [2/2]

virtual const char_type* std::ctype< char >::do_narrow | ( | const char_type * | __lo,
|  | const char_type * | __hi,
|  | char __dfault | __attribute__(__unused__),
|  | char * | __to
| ) |  | const

inline protected virtual

Narrow char array to char array.

This virtual function converts each char in the range [lo,hi) to char using the simplest reasonable transformation and writes the results to the destination array. For any char in the input that cannot be converted, dfault is used instead. For an underived ctype<char> facet, the argument will be copied unchanged.

do_narrow() is a hook for a derived facet to change the behavior of narrowing. do_narrow() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __lo | Pointer to start of range.
  __hi | Pointer to end of range.
  __dfault | Char to use if conversion fails.
  __to | Pointer to the destination array.

Returns
  __hi.

Definition at line 1157 of file locale_facets.h.

## do_tolower() [1/2]

virtual char_type std::ctype< char >::do_tolower | ( | char_type | __c | ) | const

protected virtual

Convert to lowercase.

This virtual function converts the char argument to lowercase if possible. If not possible (for example, '2'), returns the argument.

do_tolower() is a hook for a derived facet to change the behavior of lowercasing. do_tolower() must always return the same result for the same input.

Parameters

  __c | The char to convert.

Returns
  The lowercase char if convertible, else __c.

## do_tolower() [2/2]

virtual const char_type* std::ctype< char >::do_tolower | ( | char_type * | __lo,
|  | const char_type * | __hi
| ) |  | const

protected virtual

Convert array to lowercase.

This virtual function converts each char in the range [lo,hi) to lowercase if possible. Other chars remain untouched.

do_tolower() is a hook for a derived facet to change the behavior of lowercasing. do_tolower() must always return the same result for the same input.

Parameters

  __lo | Pointer to first char in range.
  __hi | Pointer to end of range.

Returns
  __hi.

## do_toupper() [1/2]

virtual char_type std::ctype< char >::do_toupper | ( | char_type | __c | ) | const

protected virtual

Convert to uppercase.

This virtual function converts the char argument to uppercase if possible. If not possible (for example, '2'), returns the argument.

do_toupper() is a hook for a derived facet to change the behavior of uppercasing. do_toupper() must always return the same result for the same input.

Parameters

  __c | The char to convert.

Returns
  The uppercase char if convertible, else __c.

## do_toupper() [2/2]

virtual const char_type* std::ctype< char >::do_toupper | ( | char_type * | __lo,
|  | const char_type * | __hi
| ) |  | const

protected virtual

Convert array to uppercase.

This virtual function converts each char in the range [lo,hi) to uppercase if possible. Other chars remain untouched.

do_toupper() is a hook for a derived facet to change the behavior of uppercasing. do_toupper() must always return the same result for the same input.

Parameters

  __lo | Pointer to start of range.
  __hi | Pointer to end of range.

Returns
  __hi.

## do_widen() [1/2]

virtual char_type std::ctype< char >::do_widen | ( | char | __c | ) | const

inline protected virtual

Widen char.

This virtual function converts the char to char using the simplest reasonable transformation. For an underived ctype<char> facet, the argument will be returned unchanged.

do_widen() is a hook for a derived facet to change the behavior of widening. do_widen() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __c | The char to convert.

Returns
  The converted character.

Definition at line 1082 of file locale_facets.h.

## do_widen() [2/2]

virtual const char* std::ctype< char >::do_widen | ( | const char * | __lo,
|  | const char * | __hi,
|  | char_type * | __to
| ) |  | const

inline protected virtual

Widen char array.

This function converts each char in the range [lo,hi) to char using the simplest reasonable transformation. For an underived ctype<char> facet, the argument will be copied unchanged.

do_widen() is a hook for a derived facet to change the behavior of widening. do_widen() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __lo | Pointer to start of range.
  __hi | Pointer to end of range.
  __to | Pointer to the destination array.

Returns
  __hi.

Definition at line 1105 of file locale_facets.h.

## is() [1/2]

bool std::ctype< char >::is | ( | mask | __m,
|  | char | __c
| ) |  | const

inline

Test char classification.

This function compares the mask table[c] to __m.

Parameters

  __c | The char to compare the mask of.
  __m | The mask to compare against.

Returns
  True if __m & table[__c] is true, false otherwise.

Definition at line 43 of file ctype_inline.h.

References std::__ctype_abstract_base< _CharT >::is().

## is() [2/2]

const char * std::ctype< char >::is | ( | const char * | __lo,
|  | const char * | __hi,
|  | mask * | __vec
| ) |  | const

inline

Return a mask array.

This function finds the mask for each char in the range [lo, hi) and successively writes it to vec. vec must have as many elements as the char array.

Parameters

  __lo | Pointer to start of range.
  __hi | Pointer to end of range.
  __vec | Pointer to an array of mask storage.

Returns
  __hi.

Definition at line 48 of file ctype_inline.h.

References std::__ctype_abstract_base< _CharT >::scan_is().

## narrow() [1/2]

char std::ctype< char >::narrow | ( | char_type | __c,
|  | char | __dfault
| ) |  | const

inline

Narrow char.

This function converts the char to char using the simplest reasonable transformation. If the conversion fails, dfault is returned instead. For an underived ctype<char> facet, c will be returned unchanged.

This function works as if it returns ctype<char>::do_narrow(c). do_narrow() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __c | The char to convert.
  __dfault | Char to return if conversion fails.

Returns
  The converted character.

Definition at line 930 of file locale_facets.h.

## narrow() [2/2]

const char_type* std::ctype< char >::narrow | ( | const char_type * | __lo,
|  | const char_type * | __hi,
|  | char | __dfault,
|  | char * | __to
| ) |  | const

inline

Narrow char array.

This function converts each char in the input to char using the simplest reasonable transformation and writes the results to the destination array. For any char in the input that cannot be converted, dfault is used instead. For an underived ctype<char> facet, the argument will be copied unchanged.

This function works as if it returns ctype<char>::do_narrow(lo, hi, dfault, to). do_narrow() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __lo | Pointer to start of range.
  __hi | Pointer to end of range.
  __dfault | Char to use if conversion fails.
  __to | Pointer to the destination array.

Returns
  __hi.

Definition at line 963 of file locale_facets.h.

## scan_is()

const char * std::ctype< char >::scan_is | ( | mask | __m,
|  | const char * | __lo,
|  | const char * | __hi
| ) |  | const

inline

Find char matching a mask.

This function searches for and returns the first char in [lo,hi) for which is(m,char) is true.

Parameters

  __m | The mask to compare against.
  __lo | Pointer to start of range.
  __hi | Pointer to end of range.

Returns
  Pointer to a matching char if found, else __hi.

Definition at line 57 of file ctype_inline.h.

References std::__ctype_abstract_base< _CharT >::scan_not().

## scan_not()

const char * std::ctype< char >::scan_not | ( | mask | __m,
|  | const char * | __lo,
|  | const char * | __hi
| ) |  | const

inline

Find char not matching a mask.

This function searches for and returns a pointer to the first char in [__lo,__hi) for which is(m,char) is false.

Parameters

  __m | The mask to compare against.
  __lo | Pointer to start of range.
  __hi | Pointer to end of range.

Returns
  Pointer to a non-matching char if found, else __hi.

Definition at line 67 of file ctype_inline.h.

## table()

const mask* std::ctype< char >::table | ( |  | ) | const
throw | ( |
| ) |  |

inline

Returns a pointer to the mask table provided to the constructor, or the default from classic_table() if none was provided.

Definition at line 981 of file locale_facets.h.

## tolower() [1/2]

char_type std::ctype< char >::tolower | ( | char_type | __c | ) | const

inline

Convert to lowercase.

This function converts the char argument to lowercase if possible. If not possible (for example, '2'), returns the argument.

tolower() acts as if it returns ctype<char>::do_tolower(__c). do_tolower() must always return the same result for the same input.

Parameters

  __c | The char to convert.

Returns
  The lowercase char if convertible, else __c.

Definition at line 835 of file locale_facets.h.

## tolower() [2/2]

const char_type* std::ctype< char >::tolower | ( | char_type * | __lo,
|  | const char_type * | __hi
| ) |  | const

inline

Convert array to lowercase.

This function converts each char in the range [lo,hi) to lowercase if possible. Other chars remain untouched.

tolower() acts as if it returns ctype<char>:: do_tolower(__lo, __hi). do_tolower() must always return the same result for the same input.

Parameters

  __lo | Pointer to first char in range.
  __hi | Pointer to end of range.

Returns
  __hi.

Definition at line 852 of file locale_facets.h.

## toupper() [1/2]

char_type std::ctype< char >::toupper | ( | char_type | __c | ) | const

inline

Convert to uppercase.

This function converts the char argument to uppercase if possible. If not possible (for example, '2'), returns the argument.

toupper() acts as if it returns ctype<char>::do_toupper(c). do_toupper() must always return the same result for the same input.

Parameters

  __c | The char to convert.

Returns
  The uppercase char if convertible, else __c.

Definition at line 802 of file locale_facets.h.

## toupper() [2/2]

const char_type* std::ctype< char >::toupper | ( | char_type * | __lo,
|  | const char_type * | __hi
| ) |  | const

inline

Convert array to uppercase.

This function converts each char in the range [__lo,__hi) to uppercase if possible. Other chars remain untouched.

toupper() acts as if it returns ctype<char>:: do_toupper(__lo, __hi). do_toupper() must always return the same result for the same input.

Parameters

  __lo | Pointer to first char in range.
  __hi | Pointer to end of range.

Returns
  __hi.

Definition at line 819 of file locale_facets.h.

## widen() [1/2]

char_type std::ctype< char >::widen | ( | char | __c | ) | const

inline

Widen char.

This function converts the char to char_type using the simplest reasonable transformation. For an underived ctype<char> facet, the argument will be returned unchanged.

This function works as if it returns ctype<char>::do_widen(c). do_widen() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __c | The char to convert.

Returns
  The converted character.

Definition at line 872 of file locale_facets.h.

## widen() [2/2]

const char* std::ctype< char >::widen | ( | const char * | __lo,
|  | const char * | __hi,
|  | char_type * | __to
| ) |  | const

inline

Widen char array.

This function converts each char in the input to char using the simplest reasonable transformation. For an underived ctype<char> facet, the argument will be copied unchanged.

This function works as if it returns ctype<char>::do_widen(c). do_widen() must always return the same result for the same input.

Note: this is not what you want for codepage conversions. See codecvt for that.

Parameters

  __lo | Pointer to first char in range.
  __hi | Pointer to end of range.
  __to | Pointer to the destination array.

Returns
  __hi.

Definition at line 899 of file locale_facets.h.

## Member Data Documentation

## id

locale::id std::ctype< char >::id

static

The facet id for ctype<char>

Definition at line 703 of file locale_facets.h.

## table_size

const size_t std::ctype< char >::table_size

static

The size of the mask table. It is SCHAR_MAX + 1.

Definition at line 705 of file locale_facets.h.

The documentation for this class was generated from the following files:

- locale_facets.h
- ctype_inline.h