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

 

C++

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Feature test macros (C++20)

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Technical specifications

Symbols index

External libraries

 

Strings library

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Classes

basic_string

basic_string_view (C++17)

char_traits

 

std::basic_string_view

Member functions basic_string_view::basic_string_view    basic_string_view::operator= Iterators basic_string_view::beginbasic_string_view::cbegin basic_string_view::endbasic_string_view::cend basic_string_view::rbeginbasic_string_view::crbegin basic_string_view::rendbasic_string_view::crend Element access basic_string_view::at basic_string_view::operator[] basic_string_view::front basic_string_view::back basic_string_view::data Capacity basic_string_view::sizebasic_string_view::length basic_string_view::max_size basic_string_view::empty Modifiers basic_string_view::remove_prefix basic_string_view::remove_suffix basic_string_view::swap

Operations basic_string_view::copy basic_string_view::substr basic_string_view::compare basic_string_view::starts_with (C++20) basic_string_view::ends_with (C++20) basic_string_view::contains (C++23) basic_string_view::find basic_string_view::rfind basic_string_view::find_first_of basic_string_view::find_last_of basic_string_view::find_first_not_of basic_string_view::find_last_not_of Constants basic_string_view::npos Non-member functions operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) operator<< operator""sv Helper classes hash<std::string_view>hash<std::wstring_view>hash<std::u8string_view>hash<std::u16string_view>hash<std::u32string_view> (C++20) Deduction guides(C++20)

 

constexpr const_reference front() const;		(since C++17)

Returns reference to the first character in the view. The behavior is undefined if empty() == true.

Parameters

(none)

Return value

reference to the first character, equivalent to operator[](0).

Complexity

Constant.

Example

Run this code

#include <string_view>
#include <iostream>
 
int main() {
    for (std::string_view str{"ABCDEF"}; !str.empty(); str.remove_prefix(1))
        std::cout << str.front() << ' ' << str << '\n';
}

Output:

A ABCDEF
B BCDEF
C CDEF
D DEF
E EF
F F

See also

back (C++17)	accesses the last character (public member function)
empty (C++17)	checks whether the view is empty (public member function)
front (C++11)	accesses the first character (public member function of std::basic_string<CharT,Traits,Allocator>)