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std::experimental::basic_string_view::basic_string_view(3) | C++ Standard Libary | std::experimental::basic_string_view::basic_string_view(3) |
NAME¶
std::experimental::basic_string_view::basic_string_view - std::experimental::basic_string_view::basic_string_view
Synopsis¶
constexpr basic_string_view() noexcept; (1) (library
fundamentals TS)
constexpr basic_string_view(const basic_string_view& (2) (library
fundamentals TS)
other) noexcept = default;
template<class Allocator>
basic_string_view(const std::basic_string<CharT, (3) (library
fundamentals TS)
Traits, Allocator>& str) noexcept;
constexpr basic_string_view(const CharT* s, size_type (4) (library
fundamentals TS)
count);
constexpr basic_string_view(const CharT* s); (5) (library fundamentals
TS)
1) Default constructor. Constructs an empty basic_string_view.
2) Copy constructor. Constructs a view of the same content as other.
3) Constructs a view of the first str.size() characters of the character
array
starting with the element pointed by str.data().
4) Constructs a view of the first count characters of the character array
starting
with the element pointed by s. s can contain null characters. The behavior is
undefined if [s, s+count) is not a valid range (even though the constructor
may not
access any of the elements of this range)
5) Constructs a view of the null-terminated character string pointed to by s,
not
including the terminating null character. The length of the view is
determined as if
by Traits::length(s). The behavior is undefined if [s, s+Traits::length(s))
is not a
valid range (even though the constructor may not access any of the elements
of this
range)
Parameters¶
other - another view to initialize the view with
str - a C++ string object to initialize view with
s - pointer to a character array or a C string to initialize the view with
count - number of characters to include in the view
Exceptions¶
4-5) Throws nothing.
Complexity¶
1-4) constant
5) linear in length of s
Example¶
// Run this code
#include <iostream>
#include <experimental/string_view>
int main()
{
std::string cppstr = "Foo";
char array[3] = {'B', 'a', 'r'};
std::experimental::string_view cppstr_v(cppstr);
std::experimental::string_view array_v(array, sizeof array);
std::experimental::wstring_view wcstr_v = L"xyzzy";
std::cout << cppstr_v << '\n'
<< array_v << '\n'
<< wcstr_v.size() << '\n';
}
Output:¶
Foo
Bar
5
See also¶
operator= assigns a view
(public member function)
2022.07.31 | http://cppreference.com |