operator+,- (ranges::elements_view:: iterator )

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Ranges library
Range adaptors
friend constexpr /*iterator*/ operator + ( const /*iterator*/ & i, difference_type n )
requires ranges:: random_access_range < Base > ;
(1) (since C++20)
friend constexpr /*iterator*/ operator + ( difference_type n, const /*iterator*/ & i )
requires ranges:: random_access_range < Base > ;
(2) (since C++20)
friend constexpr /*iterator*/ operator - ( const /*iterator*/ & i, difference_type n )
requires ranges:: random_access_range < Base > ;
(3) (since C++20)
friend constexpr difference_type operator - ( const /*iterator*/ & x,

const /*iterator*/ & y )

requires std:: sized_sentinel_for < ranges:: iterator_t < Base > , ranges:: iterator_t < Base >> ;
(4) (since C++20)
1,2) Returns the iterator i incremented by n .
3) Returns the iterator i decremented by n .
4) Returns the distance between x and y .

These functions are not visible to ordinary unqualified or qualified lookup , and can only be found by argument-dependent lookup when elements_view:: iterator <Const> is an associated class of the arguments.

Parameters

i, x, y - the iterators
n - position relative to current location

Return value

1,2) [ & ] { auto j = i ; j + = n ; return j ; } ( )
3) [ & ] { auto j = i ; j - = n ; return j ; } ( )
4) x. base ( ) - y. base ( )

Example

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3483 C++20 elements_view::iterator 's difference is overconstrained requirement is relaxed