Difference between revisions of "cpp/regex/regex search"

Revision as of 10:47, 12 January 2013

Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <regex>

</td>

<td >

template< class BidirIt,

class Alloc, class CharT, class Traits >
bool regex_search( BidirIt first, BidirIt last,
std::match_results<BidirIt,Alloc>& m,
const std::basic_regex<CharT,Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (1) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class Alloc, class CharT, class Traits >

bool regex_search( const CharT* str,
std::match_results<BidirIt,Alloc>& m,
const std::basic_regex<CharT,Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (2) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class STraits, class SAlloc,

class Alloc, class CharT, class Traits >
bool regex_search( const std::basic_string<CharT,STraits,SAlloc>& s,
std::match_results<
typename std::basic_string<CharT,STraits,SAlloc>::const_iterator,
Alloc
>& m,
const std::basic_regex<CharT, Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (3) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class BidirIt,

class CharT, class Traits >
bool regex_search( BidirIt first, BidirIt last,
const std::basic_regex<CharT,Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (4) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits >

bool regex_search( const CharT* str,
const std::basic_regex<CharT,Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (5) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class STraits, class SAlloc,

class CharT, class Traits >
bool regex_search( const std::basic_string<CharT,STraits,SAlloc>& s,
const std::basic_regex<CharT,Traits>& e,
std::regex_constants::match_flag_type flags =

std::regex_constants::match_default );

</td>

<td > (6) </td> <td > (since C++11) </td> </tr> Template:ddcl list end

1) Determines if there is a match between the regular express e and some subsequence in the target character sequence [first,last). Match results are returned in m.

2) Returns std::regex_search(str, str + std::char_traits<charT>::length(str), m, e, flags).

3) Returns std::regex_search(s.begin(), s.end(), m, e, flags).

4) The same as (1), omitting the match results.

5) Returns std::regex_search(str, str + std::char_traits<charT>::length(str), e, flags).

6) Returns std::regex_search(s.begin(), s.end(), e, flags).

first, last	-	the target character range
m	-	the match results
str	-	a target character null-terminated C-style string
s	-	a target character std::basic_string
e	-	the std::regex
flags	-	the match flags
Type requirements
- `BidirIt` must meet the requirements of LegacyBidirectionalIterator.
- `Alloc` must meet the requirements of Allocator.

Return value

Returns true if a match exists, false otherwise. In either case, the object m is updated, as follows:

If the match does not exist:

m.ready() == true
m.empty() == true
m.size() == 0

If the match exists:

m.ready()	true
m.empty()	false
m.size()	number of subexpressions plus 1, that is, 1+e.mark_count()
m.prefix().first	`first`
m.prefix().second	m[0].first
m.prefix().matched	m.prefix().first != m.prefix().second
m.suffix().first	m[0].second
m.suffix().second	`last`
m.suffix().matched	m.suffix().first != m.suffix().second
m[0].first	the start of the matching sequence
m[0].second	the end of the matching sequence
m[0].matched	true if a match was found, false otherwise
m[n].first	the start of the sequence that matched sub-expression n, or `last` if the subexpression did not participate in the match
m[n].second	the end of the sequence that matched sub-expression n, or `last` if the subexpression did not participate in the match
m[n].matched	true if sub-expression n participated in the match, false otherwise

@@ Line 83: / Line 83: @@
 ===Return value===
-Returns {{c|true}} if a match exists somewhere in the target sequence, {{c|false}} otherwise.
+Returns {{c|true}} if a match exists, {{c|false}} otherwise. In either case, the object {{tt|m}} is updated, as follows:
+If the match does not exist:
+{{dcl list begin}}
+{{dcl list item | {{c|1=m.ready() == true}} }}
+{{dcl list item | {{c|1=m.empty() == true}} }}
+{{dcl list item | {{c|1=m.size() == 0}} }}
+{{dcl list end}}
+If the match exists:
+{{dcl list begin}}
+{{dcl list item | {{c|m.ready()}} | {{c|true}} }}
+{{dcl list item | {{c|m.empty()}} | {{c|false}} }}
+{{dcl list item | {{c|m.size()}}  | number of subexpressions plus 1, that is, {{c|1+e.mark_count()}} }}
+{{dcl list item | {{c|m.prefix().first}} | {{tt|first}} }}
+{{dcl list item | {{c|m.prefix().second}} | {{c|m[0].first}} }}
+{{dcl list item | {{c|m.prefix().matched}} | {{c|m.prefix().first !{{=}} m.prefix().second}} }}
+{{dcl list item | {{c|m.suffix().first}} | {{c|m[0].second}}}}
+{{dcl list item | {{c|m.suffix().second}} | {{tt|last}}}}
+{{dcl list item | {{c|m.suffix().matched}} | {{c|m.suffix().first !{{=}} m.suffix().second}} }}
+{{dcl list item | {{c|m[0].first}} | the start of the matching sequence }}
+{{dcl list item | {{c|m[0].second}} | the end of the matching sequence }}
+{{dcl list item | {{c|m[0].matched}} | {{c|true}} if a match was found, {{c|false}} otherwise}}
+{{dcl list item | {{c|1=m[n].first}} | the start of the sequence that matched sub-expression n, or {{tt|last}} if the subexpression did not participate in the match}}
+{{dcl list item | {{c|1=m[n].second}} | the end of the sequence that matched sub-expression n, or {{tt|last}} if the subexpression did not participate in the match}}
+{{dcl list item | {{c|1=m[n].matched}} | {{c|true}} if sub-expression n participated in the match, {{c|false}} otherwise}}
+{{dcl list end}}
+===Example===
+{{example
+ | code=
+ | output=
+}}
+===See also===
+{{dcl list begin}}
+{{dcl list template | cpp/regex/dcl list basic_regex}}
+{{dcl list template | cpp/regex/dcl list match_results}}
+{{dcl list template | cpp/regex/dcl list regex_match}}
+{{dcl list end}}
 [[de:cpp/regex/regex search]]

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Classes
basic_regex (C++11)
sub_match (C++11)
match_results (C++11)
Algorithms
regex_match (C++11)
regex_search (C++11)
regex_replace (C++11)
Iterators
regex_iterator (C++11)
regex_token_iterator (C++11)
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regex_traits (C++11)
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syntax_option_type (C++11)
match_flag_type (C++11)
error_type (C++11)
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Modified ECMAScript-262 (C++11)

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Difference between revisions of "cpp/regex/regex search"

Revision as of 10:47, 12 January 2013

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