RetroSearch Browse

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from http://en.cppreference.com/w/cpp/language/attributes/../../string/basic_string_view/empty.html below:

std::basic_string_view<CharT,Traits>::empty - cppreference.com

constexpr bool empty() const noexcept;

(since C++17)

Checks if the view has no characters, i.e. whether size() == â0â.

[edit] Parameters

(none)

[edit] Return value

true if the view is empty, false otherwise.

[edit] Complexity

Constant.

[edit] Example

#include <iostream>
#include <string_view>
 
// Print a string surrounded by single quotes, its
// length and whether it is considered empty.
void check_string(std::string_view ref)
{
    std::cout << std::boolalpha
              << "'" << ref << "' has " << ref.size()
              << " character(s); emptiness: " << ref.empty() << '\n';
}
 
int main(int argc, char **argv)
{
    // An empty string
    check_string("");
 
    // Almost always not empty: argv[0]
    if (argc > 0)
        check_string(argv[0]);
}

Possible output:

'' has 0 character(s); emptiness: true
'./a.out' has 7 character(s); emptiness: false

[edit] See also returns the number of characters
(public member function) [edit] returns the maximum number of characters
(public member function) [edit] returns the size of a container or array
(function template) [edit] checks whether the container is empty
(function template) [edit] checks whether the string is empty
(public member function of std::basic_string<CharT,Traits,Allocator>) [edit]

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4