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std::regex_match
Fromcppreference.com
template
boolregex_match(BidirItfirst,BidirItlast,
std::match_results&m,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(1)
(sinceC++11)
template
boolregex_match(BidirItfirst,BidirItlast,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(2)
(sinceC++11)
template
boolregex_match(constCharT*str,
std::match_results&m,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(3)
(sinceC++11)
template
boolregex_match(conststd::basic_string&s,
std::match_results<
typenamestd::basic_string::const_iterator,
Alloc
>&m,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(4)
(sinceC++11)
template
boolregex_match(constCharT*str,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(5)
(sinceC++11)
template
boolregex_match(conststd::basic_string&s,
conststd::basic_regex&e,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default);
(6)
(sinceC++11)
template
boolregex_match(conststd::basic_string&&,
std::match_results<
typenamestd::basic_string::const_iterator,
Alloc
>&,
conststd::basic_regex&,
std::regex_constants::match_flag_typeflags=
std::regex_constants::match_default)=delete;
(7)
(sinceC++11)
Determinesiftheregularexpressionematchestheentiretargetcharactersequence,whichmaybespecifiedasstd::string,aC-string,oraniteratorpair.
1)Determinesifthereisamatchbetweentheregularexpressioneandtheentiretargetcharactersequence[first,last),takingintoaccounttheeffectofflags.Whendeterminingifthereisamatch,onlypotentialmatchesthatmatchtheentirecharactersequenceareconsidered.Matchresultsarereturnedinm.
2)Behavesas(1)above,omittingthematchresults.
3)Returnsstd::regex_match(str,str+std::char_traits::length(str),m,e,flags).
4)Returnsstd::regex_match(s.begin(),s.end(),m,e,flags).
5)Returnsstd::regex_match(str,str+std::char_traits::length(str),e,flags).
6)Returnsstd::regex_match(s.begin(),s.end(),e,flags).
7)Theoverload(4)isprohibitedfromacceptingtemporarystrings,otherwisethisfunctionpopulatesmatch_resultsmwithstringiteratorsthatbecomeinvalidimmediately.
Notethatregex_matchwillonlysuccessfullymatcharegularexpressiontoanentirecharactersequence,whereasstd::regex_searchwillsuccessfullymatchsubsequences.
Contents
1Parameters
2Returnvalue
3Notes
4Example
5Defectreports
6Seealso
[edit]Parameters
first,last
-
thetargetcharacterrangetoapplytheregexto,givenasiterators
m
-
thematchresults
str
-
thetargetstring,givenasanull-terminatedC-stylestring
s
-
thetargetstring,givenasastd::basic_string
e
-
theregularexpression
flags
-
flagsusedtodeterminehowthematchwillbeperformed
Typerequirements
-BidirItmustmeettherequirementsofLegacyBidirectionalIterator.
[edit]Returnvalue
Returnstrueifamatchexists,falseotherwise.Ineithercase,theobjectmisupdated,asfollows:
Ifthematchdoesnotexist:
m.ready()==true
m.empty()==true
m.size()==0
Ifthematchexists:
m.ready()
true
m.empty()
false
m.size()
numberofmarkedsubexpressionsplus1,thatis,1+e.mark_count()
m.prefix().first
first
m.prefix().second
first
m.prefix().matched
false(thematchprefixisempty)
m.suffix().first
last
m.suffix().second
last
m.suffix().matched
false(thematchsuffixisempty)
m[0].first
first
m[0].second
last
m[0].matched
true(theentiresequenceismatched)
m[n].first
thestartofthesequencethatmatchedmarkedsub-expressionn,orlastifthesubexpressiondidnotparticipateinthematch
m[n].second
theendofthesequencethatmatchedmarkedsub-expressionn,orlastifthesubexpressiondidnotparticipateinthematch
m[n].matched
trueifsub-expressionnparticipatedinthematch,falseotherwise
[edit]Notes
Becauseregex_matchonlyconsidersfullmatches,thesameregexmaygivedifferentmatchesbetweenregex_matchandstd::regex_search:
std::regexre("Get|GetValue");
std::cmatchm;
std::regex_search("GetValue",m,re);//returnstrue,andm[0]contains"Get"
std::regex_match("GetValue",m,re);//returnstrue,andm[0]contains"GetValue"
std::regex_search("GetValues",m,re);//returnstrue,andm[0]contains"Get"
std::regex_match("GetValues",m,re);//returnsfalse
[edit]Example
Runthiscode
#include
#include
#include
intmain()
{
//Simpleregularexpressionmatching
conststd::stringfnames[]={"foo.txt","bar.txt","baz.dat","zoidberg"};
conststd::regextxt_regex("[a-z]+\\.txt");
for(constauto&fname:fnames){
std::cout<
C++ regex find all matches