21 Strings library [strings]

21.3 String classes [string.classes]

21.3.2 Class template basic_string [basic.string]

21.3.2.7 String operations [string.ops]

21.3.2.7.5 basic_string::starts_with [string.starts.with]

constexpr bool starts_with(basic_string_view<charT, traits> x) const noexcept;
constexpr bool starts_with(charT x) const noexcept;
constexpr bool starts_with(const charT* x) const;

Effects: Equivalent to:

return basic_string_view<charT, traits>(data(), size()).starts_with(x);