std::regex_iterator<BidirIt,CharT,Traits>::regex_iterator
regex_iterator(); |
(1) | (since C++11) |
regex_iterator( BidirIt a, BidirIt b, const regex_type& re, std::regex_constants::match_flag_type m = std::regex_constants::match_default ); |
(2) | (since C++11) |
regex_iterator( const regex_iterator& ); |
(3) | (since C++11) |
regex_iterator( BidirIt, BidirIt, const regex_type&&, std::regex_constants::match_flag_type = std::regex_constants::match_default ) = delete; |
(4) | (since C++11) |
Constructs a new regex_iterator
:
1) Default constructor. Constructs an end-of-sequence iterator.
2) Constructs a
regex_iterator
from the sequence of characters
[a, b)
, the regular expression
re
, and a flag
m
that governs matching behavior. This constructor performs an initial call to
std::regex_search
with this data. If the result of this initial call is
false
,
*this
is set to an end-of-sequence iterator.
3) Copies a
regex_iterator
.
4) The overload
(2) is not allowed to be called with a temporary regex, since the returned iterator would be immediately invalidated.
Parameters
a | - | LegacyBidirectionalIterator to the beginning of the target character sequence |
b | - | LegacyBidirectionalIterator to the end of the target character sequence |
re | - | regular expression used to search the target character sequence |
m | - | flags that govern the behavior of re |
Example
#include <iostream> #include <regex> #include <string_view> int main() { constexpr std::string_view str{"#ONE:*p=&Mass; #Two:MOV %rd,42"}; const std::regex re("[a-w]"); // create regex_iterator, overload (2) auto it = std::regex_iterator<std::string_view::iterator>{ str.cbegin(), str.cend(), re // re is lvalue; if an immediate expression was used // instead, e.g. std::regex{"[a-z]"}, this would // produce an error - overload (4) is deleted }; for (decltype(it) last /* overload (1) */; it != last; ++it) std::cout << (*it).str(); }
Output:
password
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 2332 | C++11 | a regex_iterator constructed from a temporarybasic_regex became invalid immediately |
such construction is disallowed via a deleted overload |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/regex/regex_iterator/regex_iterator