basic_regex::operator=
Assigns a value to the regular expression object.
Syntax
basic_regex& operator=(const basic_regex& right);
basic_regex& operator=(const Elem *str);
template<class STtraits, class STalloc>
basic_regex& operator=(const basic_string<Elem, STtraits, STalloc>& str);
Parameters
STtraits
Traits class for a string source.STalloc
Allocator class for a string source.right
Regex source to copy.str
String to copy.
Remarks
The operators each replace the regular expression held by *this with the regular expression described by the operand sequence, then return *this.
Example
// std_tr1__regex__basic_regex_operator_as.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>
int main()
{
std::regex::value_type elem = 'x';
std::regex::flag_type flag = std::regex::grep;
elem = elem; // to quiet "unused" warnings
flag = flag;
// constructors
std::regex rx0;
std::cout << "match(\"abc\", \"\") == " << std::boolalpha
<< regex_match("abc", rx0) << std::endl;
std::regex rx1("abcd", std::regex::ECMAScript);
std::cout << "match(\"abc\", \"abcd\") == " << std::boolalpha
<< regex_match("abc", rx1) << std::endl;
std::regex rx2("abcd", 3);
std::cout << "match(\"abc\", \"abc\") == " << std::boolalpha
<< regex_match("abc", rx2) << std::endl;
std::regex rx3(rx2);
std::cout << "match(\"abc\", \"abc\") == " << std::boolalpha
<< regex_match("abc", rx3) << std::endl;
std::string str("abcd");
std::regex rx4(str);
std::cout << "match(string(\"abcd\"), \"abc\") == " << std::boolalpha
<< regex_match("abc", rx4) << std::endl;
std::regex rx5(str.begin(), str.end() - 1);
std::cout << "match(string(\"abc\"), \"abc\") == " << std::boolalpha
<< regex_match("abc", rx5) << std::endl;
std::cout << std::endl;
// assignments
rx0 = "abc";
rx0 = rx1;
rx0 = str;
rx0.assign("abcd", std::regex::ECMAScript);
rx0.assign("abcd", 3);
rx0.assign(rx1);
rx0.assign(str);
rx0.assign(str.begin(), str.end() - 1);
rx0.swap(rx1);
// mark_count
std::cout << "\"abc\" mark_count == "
<< std::regex("abc").mark_count() << std::endl;
std::cout << "\"(abc)\" mark_count == "
<< std::regex("(abc)").mark_count() << std::endl;
// locales
std::regex::locale_type loc = rx0.imbue(std::locale());
std::cout << "getloc == imbued == " << std::boolalpha
<< (loc == rx0.getloc()) << std::endl;
return (0);
}
match("abc", "") == false
match("abc", "abcd") == false
match("abc", "abc") == true
match("abc", "abc") == true
match(string("abcd"), "abc") == false
match(string("abc"), "abc") == true
"abc" mark_count == 0
"(abc)" mark_count == 1
getloc == imbued == true
Requirements
Header: <regex>
Namespace: std