std::span<T,Extent>::front

 

C++

Language

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Named requirements

Language support library

Concepts library (C++20)

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Regular expressions library (C++11)

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Technical Specifications

 

Containers library

array (C++11)

vector

deque

forward_list (C++11)

list

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span (C++20)

 

std::span

Member functions

span::span

span::operator=

Element access

span::front

span::back

span::operator[]

span::data

Iterators

span::beginspan::cbegin

span::endspan::cend

span::rbeginspan::crbegin

span::rendspan::crend

Observers

span::empty

span::size

span::size_bytes

Subviews

span::first

span::last

span::subspan

Non-member functions

as_bytesas_writable_bytes

begin(std::span)end(std::span)

get

Non-member constant

dynamic_extent

Helper classes

tuple_size

tuple_element

Deduction guides

 

constexpr reference front() const;

Returns a reference to the first element in the span.

Calling front on an empty span results in undefined behavior.

Parameters

(none)

Return value

A reference to the first element.

Complexity

Constant

Notes

For a span c, the expression c.front() is equivalent to *c.begin().

See also

back	access the last element (public member function)