(C++) Inserter

 

This page is about two different inserters:

1. Inserters (general): an output iterator that inserts elements in a container
2. std::inserter: a type of inserter that inserts at a certain iterator

 

There are three types of inserters:

1. std::back_inserter
2. std::front_inserter
3. std::inserter

 

Inserters can be found in the header file iterator.h.

 

 

 

 

 

Example

 

• Download the Qt Creator project 'CppInserters' (zip)

 

 

 

 

 

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 12.10 (quantal)

IDE(s):

• Qt Creator 2.5.2

Project type:

• Console application

C++ standard:

• C++11

Compiler(s):

• G++ 4.7.2

Libraries used:

• STL: GNU ISO C++ Library, version 4.7.2

 

 

 

 

 

Qt project file: CppInserters.pro

 

---

TEMPLATE = app CONFIG += console CONFIG -= qt QMAKE_CXXFLAGS += -std=c++11 SOURCES += main.cpp

 

 

 

 

 

main.cpp

 

---

#include <algorithm> #include <cassert> #include <list> #include <set> #include <vector> int main() {   {     //std::back_inserter: applies push_back     std::vector<int> w { 0,1,2 };     const std::vector<int> to_append { 3,4,5 };     std::copy(to_append.begin(),to_append.end(),std::back_inserter(w));     const std::vector<int> expected { 0,1,2,3,4,5 };     assert(w == expected);   }   {     //std::front_inserter: applies push_front     std::list<int> w { 3,4,5 };     const std::list<int> to_prepend { 2,1,0 }; //Must be reversed     std::copy(to_prepend.begin(),to_prepend.end(),std::front_inserter(w));     const std::list<int> expected { 0,1,2,3,4,5 };     assert(w == expected);   }   {     //std::inserter: applies insert     std::set<int> w { 1,3,5 }; //Don't care about the order     const std::set<int> to_insert { 4,0,2 }; //Don't care about the order     std::copy(to_insert.begin(),to_insert.end(),std::inserter(w,w.begin()));     const std::set<int> expected { 0,1,2,3,4,5 };     assert(w == expected);   } }