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std::basic_..._view::empty(3)  C++ Standard Libary std::basic_..._view::empty(3)

NAME
     std::basic_string_view::empty - std::basic_string_view::empty

Synopsis
	constexpr bool empty() const noexcept;		      (since C++17)
							      (until C++20)
	[[nodiscard]] constexpr bool empty() const noexcept;  (since C++20)

	Checks if the view has no characters, i.e. whether size() == 0.

Parameters
	(none)

Return value
	true if the view is empty, false otherwise.

Complexity
	Constant.

Example
     // Run this code

      #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

See also
	size	 returns the number of characters
	length	 (public member function)
	max_size returns the maximum number of characters
		 (public member function)
	size
	ssize	 returns the size of a container or array
	(C++17)  (function template)
	(C++20)
	empty	 checks whether the container is empty
	(C++17)  (function template)
		 checks whether the string is empty
	empty	 (public member function of std::basic_string<CharT,Traits,Allo-
     cator>)

http://cppreference.com 	   2024.06.10	   std::basic_..._view::empty(3)
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