std::regex_traits< _Ch_type > Struct Template Reference
[Regular Expressions]

List of all members.

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Detailed Description

template<typename _Ch_type>
struct std::regex_traits< _Ch_type >

A regular expression traits class that satisfies the requirements of tr1 section [7.2].

The class regex is parameterized around a set of related types and functions used to complete the definition of its semantics. This class satisfies the requirements of such a traits class.

Definition at line 352 of file tr1_impl/regex.

Public Types

• typedef std::ctype_base::mask char_class_type
• typedef _Ch_type char_type
• typedef std::locale locale_type
• typedef std::basic_string<
  char_type > string_type

Public Member Functions

• locale_type getloc () const
• locale_type imbue (locale_type __loc)
• bool isctype (_Ch_type __c, char_class_type __f) const
• template<typename _Fwd_iter> char_class_type lookup_classname (_Fwd_iter __first, _Fwd_iter __last) const
• template<typename _Fwd_iter> string_type lookup_collatename (_Fwd_iter __first, _Fwd_iter __last) const
• regex_traits ()
• template<typename _Fwd_iter> string_type transform (_Fwd_iter __first, _Fwd_iter __last) const
• template<typename _Fwd_iter> string_type transform_primary (_Fwd_iter __first, _Fwd_iter __last) const
• char_type translate (char_type __c) const
• char_type translate_nocase (char_type __c) const
• int value (_Ch_type __ch, int __radix) const

Static Public Member Functions

• static std::size_t length (const char_type *__p)

Protected Attributes

• locale_type _M_locale

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Constructor & Destructor Documentation

template<typename _Ch_type>

std::regex_traits< _Ch_type >::regex_traits

(

)

[inline]

Constructs a default traits object.

Definition at line 364 of file tr1_impl/regex.

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Member Function Documentation

template<typename _Ch_type>

locale_type std::regex_traits< _Ch_type >::getloc

(

)

const [inline]

Gets a copy of the current locale in use by the regex_traits object.

Definition at line 600 of file tr1_impl/regex.

References std::regex_traits< _Ch_type >::_M_locale.

template<typename _Ch_type>

locale_type std::regex_traits< _Ch_type >::imbue

(

locale_type

__loc

)

[inline]

Imbues the regex_traits object with a copy of a new locale.

Parameters:

loc

A locale.

Returns:

a copy of the previous locale in use by the regex_traits object.

Note:

Calling imbue with a different locale than the one currently in use invalidates all cached data held by *this.

Definition at line 589 of file tr1_impl/regex.

References std::regex_traits< _Ch_type >::_M_locale, and std::swap().

template<typename _Ch_type>

bool std::regex_traits< _Ch_type >::isctype	(	_Ch_type	__c,
		char_class_type	__f
	)			const [inline]

Determines if c is a member of an identified class.

Parameters:

	c	a character.
	f	a class type (as returned from lookup_classname).

Returns:

true if the character c is a member of the classification represented by f, false otherwise.

Exceptions:

std::bad_cast

if the current locale does not have a ctype facet.

Definition at line 529 of file tr1_impl/regex.

References std::regex_traits< _Ch_type >::_M_locale, std::__ctype_abstract_base< _CharT >::is(), std::regex_traits< _Ch_type >::lookup_classname(), std::use_facet(), and std::__ctype_abstract_base< _CharT >::widen().

template<typename _Ch_type>

static std::size_t std::regex_traits< _Ch_type >::length

(

const char_type *

__p

)

[inline, static]

Gives the length of a C-style string starting at __p.

Parameters:

__p

a pointer to the start of a character sequence.

Returns:

the number of characters between *__p and the first default-initialized value of type char_type. In other words, uses the C-string algorithm for determining the length of a sequence of characters.

Definition at line 378 of file tr1_impl/regex.

template<typename _Ch_type>

template<typename _Fwd_iter>

char_class_type std::regex_traits< _Ch_type >::lookup_classname	(	_Fwd_iter	__first,
		_Fwd_iter	__last
	)			const [inline]

Maps one or mire characters to a named character classification.

Parameters:

	first	beginning of the character sequence.
	last	one-past-the-end of the character sequence.

Returns:

an unspecified value that represents the character classification named by the character sequence designated by the iterator range [first, last). The value returned shall be independent of the case of the characters in the character sequence. If the name is not recognized then returns a value that compares equal to 0.

At least the following names (or their wide-character equivalent) are supported.

• d
• w
• s
• alnum
• alpha
• blank
• cntrl
• digit
• graph
• lower
• print
• punct
• space
• upper
• xdigit

Todo:

Implement this function.

Definition at line 513 of file tr1_impl/regex.

Referenced by std::regex_traits< _Ch_type >::isctype().

template<typename _Ch_type>

template<typename _Fwd_iter>

string_type std::regex_traits< _Ch_type >::lookup_collatename	(	_Fwd_iter	__first,
		_Fwd_iter	__last
	)			const [inline]

Gets a collation element by name.

Parameters:

	first	beginning of the collation element name.
	last	one-past-the-end of the collation element name.

Returns:

a sequence of one or more characters that represents the collating element consisting of the character sequence designated by the iterator range [first, last). Returns an empty string if the character sequence is not a valid collating element.

Todo:

Implement this function.

Definition at line 475 of file tr1_impl/regex.

template<typename _Ch_type>

template<typename _Fwd_iter>

string_type std::regex_traits< _Ch_type >::transform	(	_Fwd_iter	__first,
		_Fwd_iter	__last
	)			const [inline]

Gets a sort key for a character sequence.

Parameters:

	first	beginning of the character sequence.
	last	one-past-the-end of the character sequence.

Returns a sort key for the character sequence designated by the iterator range [F1, F2) such that if the character sequence [G1, G2) sorts before the character sequence [H1, H2) then v.transform(G1, G2) < v.transform(H1, H2).

What this really does is provide a more efficient way to compare a string to multiple other strings in locales with fancy collation rules and equivalence classes.

Returns:

a locale-specific sort key equivalent to the input range.

Exceptions:

std::bad_cast

if the current locale does not have a collate facet.

Definition at line 431 of file tr1_impl/regex.

References std::regex_traits< _Ch_type >::_M_locale, std::basic_string< _CharT, _Traits, _Alloc >::data(), std::basic_string< _CharT, _Traits, _Alloc >::size(), std::collate< _CharT >::transform(), and std::use_facet().

template<typename _Ch_type>

template<typename _Fwd_iter>

string_type std::regex_traits< _Ch_type >::transform_primary	(	_Fwd_iter	__first,
		_Fwd_iter	__last
	)			const [inline]

Dunno.

Parameters:

	first	beginning of the character sequence.
	last	one-past-the-end of the character sequence.

Effects: if typeid(use_facet<collate<_Ch_type> >) == typeid(collate_byname<_Ch_type>) and the form of the sort key returned by collate_byname<_Ch_type>::transform(first, last) is known and can be converted into a primary sort key then returns that key, otherwise returns an empty string. WTF??

Todo:

Implement this function.

Definition at line 457 of file tr1_impl/regex.

template<typename _Ch_type>

char_type std::regex_traits< _Ch_type >::translate

(

char_type

__c

)

const [inline]

Performs the identity translation.

Parameters:

c

A character to the locale-specific character set.

Returns:

c.

Definition at line 389 of file tr1_impl/regex.

template<typename _Ch_type>

char_type std::regex_traits< _Ch_type >::translate_nocase

(

char_type

__c

)

const [inline]

Translates a character into a case-insensitive equivalent.

Parameters:

c

A character to the locale-specific character set.

Returns:

the locale-specific lower-case equivalent of c.

Exceptions:

std::bad_cast

if the imbued locale does not support the ctype facet.

Definition at line 402 of file tr1_impl/regex.

References std::regex_traits< _Ch_type >::_M_locale, std::tolower(), and std::use_facet().

template<typename _Ch_type>

int std::regex_traits< _Ch_type >::value	(	_Ch_type	__ch,
		int	__radix
	)			const

Converts a digit to an int.

Parameters:

	ch	a character representing a digit.
	radix	the radix if the numeric conversion (limited to 8, 10, or 16).

Returns:

the value represented by the digit ch in base radix if the character ch is a valid digit in base radix; otherwise returns -1.

Todo:

Implement this function.

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The documentation for this struct was generated from the following file:

• tr1_impl/regex

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