Namespaces
Variants
Views
Actions

Difference between revisions of "cpp/regex/sub match"

From cppreference.com
< cpp‎ | regex
m (Use since= and until= params of {{ddcl}} template.)
(Member objects: use {{dsc mem obj}})
Line 44: Line 44:
 
===Member objects===
 
===Member objects===
 
{{dsc begin}}
 
{{dsc begin}}
{{dsc| {{tt|matched}} | Indicates if this match was successful.}}
+
{{dsc mem obj | nolink=true | {{dsc small|bool}} matched | Indicates if this match was successful}}
 
{{dsc end}}
 
{{dsc end}}
 
{{inherited | [[cpp/utility/pair | {{small|std::}}pair]] |
 
{{inherited | [[cpp/utility/pair | {{small|std::}}pair]] |
 
{{dsc begin}}
 
{{dsc begin}}
{{dsc| {{tt|first}} | Start of the match sequence.}}
+
{{dsc mem obj | nolink=true | {{dsc small|BidirIt}} first | Start of the match sequence.}}
{{dsc| {{tt|second}} | One-past-the-end of the match sequence.}}
+
{{dsc mem obj | nolink=true | {{dsc small|BidirIt}} second | One-past-the-end of the match sequence.}}
 
{{dsc end}}
 
{{dsc end}}
 
}}
 
}}

Revision as of 04:35, 26 September 2014

Defined in header <regex>
template<

    class BidirIt

> class sub_match;
(since C++11)

The class template sub_match is used by the regular expression engine to denote sequences of characters matched by marked sub-expressions. A match is a [begin, end) pair within the target range matched by the regular expression, but with additional observer functions to enhance code clarity.

Only the default constructor is publicly accessible. Instances of sub_match are normally constructed and populated as a part of a std::match_results container during the processing of one of the regex algorithms.

The member functions return defined default values unless the matched member is true.

sub_match inherits from std::pair<BidirIt, BidirIt>, although it cannot be treated as a std::pair object because member functions such as swap and assignment will not work as expected.

Contents

Type requirements

Template:par req concept

Specializations

Several specializations for common character sequence types are provided:

Defined in header <regex>
Type Definition
csub_match sub_match<const char*>
wcsub_match sub_match<const wchar_t*>
ssub_match sub_match<std::string::const_iterator>
wssub_match sub_match<std::wstring::const_iterator>

Member types

Member type Definition
iterator BidirIt
value_type std::iterator_traits<BidirIt>::value_type
difference_type std::iterator_traits<BidirIt>::difference_type
string_type std::basic_string<value_type>

Member objects

bool matched
Indicates if this match was successful
(public member object)

Inherited from std::pair

BidirIt first
Start of the match sequence.
(public member object)
BidirIt second
One-past-the-end of the match sequence.
(public member object)

Member functions

constructs the match object
(public member function) [edit]
Observers
returns the length of the match (if any)
(public member function) [edit]
converts to the underlying string type
(public member function) [edit]
compares matched subsequence (if any)
(public member function) [edit]

Non-member functions

(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++20)
compares a sub_match with another sub_match, a string, or a character
(function template) [edit]
outputs the matched character subsequence
(function template)

See also

iterates through regex submatches
(class template)