Namespaces
Variants
Views
Actions

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

From cppreference.com
 
 
 
 
constexpr const_reference at(size_type pos) const;
(since C++17)

Returns a const reference to the character at specified location pos. Bounds checking is performed, exception of type std::out_of_range will be thrown on invalid access.

Contents

[edit] Parameters

pos - position of the character to return

[edit] Return value

Const reference to the requested character.

[edit] Exceptions

Throws std::out_of_range if pos >= size().

[edit] Complexity

Constant.

[edit] Example

#include <iostream>
#include <stdexcept>
#include <string_view>
 
int main()
{
    std::string_view str_view("abcdef");
 
    try {
        for (std::size_t i = 0; true; ++i)
            std::cout << i << ": " << str_view.at(i) << '\n';
    }
    catch (const std::out_of_range& e) {
        std::cout << "Whooops. Index is out of range.\n";
        std::cout << e.what() << '\n';
    }
}

Possible output:

0: a
1: b
2: c
3: d
4: e
5: f
6: Whooops. Index is out of range.
basic_string_view::at: __pos (which is 6) >= this->size() (which is 6)

[edit] See also

accesses the specified character
(public member function) [edit]