std::experimental::basic_string_view<CharT,Traits>::basic_string_view

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C++
 
Technical specifications
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Library fundamentals
 
std::experimental::basic_string_view
 
constexpr basic_string_view() noexcept;
 (1) (library fundamentals TS)
constexpr basic_string_view(const basic_string_view& other) noexcept = default;
 (2) (library fundamentals TS)
template<class Allocator>
basic_string_view(const std::basic_string<CharT, Traits, Allocator>& str) noexcept;
 (3) (library fundamentals TS)
constexpr basic_string_view(const CharT* s, size_type count);
 (4) (library fundamentals TS)
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

 assigns a view
(public member function)
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