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

constexpr bool starts_with(basic_string_view x) const noexcept;
 (1) (since C++20) 
constexpr bool starts_with(CharT x) const noexcept;
 (2) (since C++20) 
constexpr bool starts_with(const CharT* x) const;
 (3) (since C++20)

Checks if the string view begins with the given prefix, where.

1) the prefix is a string view. Effectively returns size() >= x.size() && compare(0, x.size(), x) == 0
2) the prefix is a single character. Effectively returns !empty() && Traits::eq(front(), x)
3) the prefix is a C-style string. Effectively returns starts_with(basic_string_view(x))

Parameters

x - a character sequence or a single character to compare to the start of the string view

Return value

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

Example

See also

(C++20)
 checks if the string view ends with the given suffix
(public member function)
(C++20)
 checks if the string starts with the given prefix
(public member function of std::basic_string<CharT,Traits,Allocator>)
(C++20)
 checks if the string ends with the given suffix
(public member function of std::basic_string<CharT,Traits,Allocator>)
compares two views
(public member function)

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