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C++

Reference

<iterator>

move_iterator

public member function
<iterator>

std::move_iterator::operator-=

move_iterator& operator-= (difference_type n);
Decrease iterator
Decreases the move_iterator by n element positions.

Internally, the function simply reflects the operation into its base iterator .

Note that this function requires the base iterator to be a random-access iterator.

Parameters

n
Number of elements to offset backwards.
Member type difference_type is an alias of the base iterator's own difference type.

Return value

The move iterator itself (*this).

Data races

Modifies the object.
The iterator returned can be used to access or modify pointed elements.

Exception safety

Provides the same level of guarantee as decreasing the base iterator.

See also

move_iterator::operator+=
Advance iterator (public member function)
move_iterator::operator--
Decrease iterator position (public member function)
move_iterator::operator-
Subtraction operator (public member function)