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std::basic_...starts_with(3)   C++ Standard Libary  std::basic_...starts_with(3)

NAME
     std::basic_string::starts_with - std::basic_string::starts_with

Synopsis
	constexpr bool
	    starts_with(  std::basic_string_view<CharT,Traits>	sv ) const   (1)
     (since C++20)
	noexcept;
	constexpr  bool 						     (2)
     (since C++20)
	    starts_with( CharT ch ) const noexcept;
	constexpr  bool 						     (3)
     (since C++20)
	    starts_with( const CharT* s ) const;

	Checks if the string begins with the given prefix. The prefix may be one
     of the
	following:

	1) A string view sv (which may be a result of implicit	conversion  from
     another
	std::basic_string).
	2) A single character ch.
	3) A null-terminated character string s.

	All  three  overloads  effectively  return std::basic_string_view<CharT,
     Traits>(data(),
	size()).starts_with(x), where x is the parameter.

Parameters
	sv - a string view which may be a result of implicit conversion from an-
     other
	     std::basic_string
	ch - a single character
	s  - a null-terminated character string

Return value
	true if the string begins with the provided prefix, false otherwise.

Notes
	    Feature-test macro	    Value    Std		    Feature
	__cpp_lib_starts_ends_with 201711L  (C++20)  String  prefix  and  suffix
     checking:
						   starts_with() and ends_with()

Example
     // Run this code

      #include <cassert>
      #include <string>
      #include <string_view>

      int main()
      {
	  using namespace std::literals;

	  const auto str = "Hello, C++20!"s;

	  assert
	  (""
	      && str.starts_with("He"sv)  // (1)
	      && !str.starts_with("he"sv) // (1)
	      &&  str.starts_with("He"s)    // (1) implicit conversion string to
     string_view
	      && !str.starts_with("he"s)  // (1) implicit conversion  string  to
     string_view
	      && str.starts_with('H')	  // (2)
	      && !str.starts_with('h')	  // (2)
	      && str.starts_with("He")	  // (3)
	      && !str.starts_with("he")   // (3)
	  );
      }

See also
	ends_with   checks if the string ends with the given suffix
	(C++20)     (public member function)
	starts_with checks if the string view starts with the given prefix
	(C++20) 	 (public      member	  function	of	std::ba-
     sic_string_view<CharT,Traits>)
	ends_with   checks if the string view ends with the given suffix
	(C++20) 	 (public      member	  function	of	std::ba-
     sic_string_view<CharT,Traits>)
	contains    checks if the string contains the given substring or charac-
     ter
	(C++23)     (public member function)
	contains     checks  if  the string view contains the given substring or
     character
	(C++23) 	 (public      member	  function	of	std::ba-
     sic_string_view<CharT,Traits>)
	compare     compares two strings
		    (public member function)
	substr	    returns a substring
		    (public member function)

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