cpp/iterator/back insert iterator: Difference between revisions

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{{ddcl list header | iterator}}

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class back_insert_iterator : public std::iterator< std::output_iterator_tag,

                                                  void,void,void,void >

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{{tt|std::back_insert_iterator}} is an output iterator that appends to a container for which it was constructed, using the container's {{tt|push_back()}} member function whenever the iterator (whether dereferenced or not) is assigned to. Incrementing the {{tt|std::back_insert_iterator}} is a no-op.

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{{dcl list hitem | Member type | Definition}}

{{dcl list item | {{tt|container_type}} | {{tt|Container}}}}

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{{dcl list template | cpp/iterator/inserter/dcl list constructor | back_insert_iterator}}

{{dcl list template | cpp/iterator/inserter/dcl list operator{{=}} | back_insert_iterator}}

{{dcl list template | cpp/iterator/inserter/dcl list operator* | back_insert_iterator}}

{{dcl list template | cpp/iterator/inserter/dcl list operator++ | back_insert_iterator}}

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{{dcl list hitem | Member name | Definition}}

{{dcl list item | {{tt|container}} {{mark|protected}} | a pointer of type {{tt|Container*}} }}

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{{cpp/iterator/iterator/inherit|std::output_iterator_tag|void|void|void|void}}

| code=

#include <algorithm>

     std::generate_n(std::back_insert_iterator<std::vector<int>>(v), // can be simplified

                    10, [](){return std::rand()%10;});             // with std::back_inserter

     for(int n : v)

| output=

3 6 7 5 3 5 6 2 9 1

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{{dcl list template | cpp/iterator/dcl list back_inserter}}

{{dcl list template | cpp/iterator/dcl list front_insert_iterator}}

{{dcl list template | cpp/iterator/dcl list insert_iterator}}

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