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

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C++
Ranges library
Range adaptors
std::ranges::enumerate_view
Member functions
Deduction guides
Nested classes
Iterator
operator+ (enumerate_view:: iterator )
operator- (enumerate_view:: iterator )
Sentinel
friend constexpr /* iterator */

operator + ( const /* iterator */ & i, difference_type n )

requires ranges:: random_access_range < /* Base */ > ;
(1) (since C++23)
friend constexpr /* iterator */

operator + ( difference_type n, const /* iterator */ & i )

requires ranges:: random_access_range < /* Base */ > ;
(2) (since C++23)
friend constexpr /* iterator */

operator - ( const /* iterator */ & i, difference_type n )

requires ranges:: random_access_range < /* Base */ > ;
(3) (since C++23)
friend constexpr difference_type
operator - ( const /* iterator */ & i, const /* iterator */ & j ) noexcept ;
(4) (since C++23)

Performs iterator arithmetic or calculates the distance.

pos_ is the underlying index, and Base is the (possibly const-qualified) type of underlying view.

Equivalent to:

1) auto temp = i ; temp + = n ; return temp ;
2) return i + n ;
3) auto temp = i ; temp - = n ; return temp ;
4) return i. pos_ - j. pos_ ;

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

Parameters

i, j - the iterators
n - position relative to current location

Return value

1,2) An incremented iterator.
3) A decremented iterator.
4) A distance between given iterators.

Example

This section is incomplete
Reason: no 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 3912 C++23 overload (4) was not noexcept it is noexcept

See also

advances or decrements the underlying iterator
(public member function)
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