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    <p>Try:</p> <pre><code>int main() { std::deque&lt;std::string&gt; mydeque; std::ifstream myifstream("test.txt"); std::string line; while(std::getline(myifstream, line) { mydeque.push_back(line); } } </code></pre> <p>If it is one word per line you can simplify to:</p> <pre><code>int main() { std::deque&lt;std::string&gt; mydeque; std::ifstream myifstream("test.txt"); // Note: istream_iterator&lt;T&gt; uses std::istream&amp; operator&gt;&gt;(std::istream&amp;, T&amp;) to // read data from the stream. If `T` is a std::string this means it will // read a single space separated word. std::copy(std::istream_iterator&lt;std::string&gt;(myifstream), std::istream_iterator&lt;std::string&gt;(), std::back_inserter(mydeque) ); } </code></pre> <p>If each line contains multiple words and you want to use the back inserter then you need to define a class for reading a whole line in an object that can be used with iterators:</p> <pre><code>struct Line { std::string data; operator std::string const&amp;() const {return data;} friend std::istream&amp; operator&gt;&gt;(std::istream&amp; s, Line&amp; dst) { return std::getline(s, dst.data); } }; int main() { std::deque&lt;std::string&gt; mydeque; std::ifstream myifstream("test.txt"); std::copy(std::istream_iterator&lt;Line&gt;(myifstream), std::istream_iterator&lt;Line&gt;(), std::back_inserter(mydeque) ); } </code></pre> <p>Or we can just use the constructrs:</p> <pre><code>int main() { std::ifstream myifstream("test.txt"); std::deque&lt;std::string&gt; mydeque(std::istream_iterator&lt;Line&gt;(myifstream), (std::istream_iterator&lt;Line&gt;())); // Note: Extra brace required around second iterator here // This is to avoid the problem with the `Most Vexing Parse` // Which would otherwise make this a function declaration } </code></pre>
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    1. POstd::getline does not accept std::back_insert_iterator
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    1. USMartin York
    1. USMartin York
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    1. POstd::getline does not accept std::back_insert_iterator
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    1. COThat would probably work. Any idea, why the dereferenced insert_iterator behaves different than an assignable string object? Because *myback_insert_iterator = "abc"; actually works fine.
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      1. USSimon1X
    2. CO@Simon1X: A [back insert iterator](http://www.sgi.com/tech/stl/back_insert_iterator.html) is an [output iterator](http://www.sgi.com/tech/stl/OutputIterator.html). Technically you must use the ++ operator after each use of the assignment operator on the value (see note 3 in the Output Iterator page). Not incrementing after assignment is undefined behavior. It boils down to the output iterator does not have a value type thus operator * does not return a reference to std::string (the actual type is undefined). The iterator is defined in terms of the expected outputs in relation to the operators.
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      1. USMartin York
    3. CO@simon1X C++ is a statically typed language. The compiler does not *know* about behavior, it knows the language constructs and types, and the iterator is not a string. `getline` takes a string as argument, and while the subset of operations that you need could be applied to that iterator (or many other types), the compiler will reject it on the ground that no matter how loud it *quacks* it is not a *duck*
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      1. USDavid Rodríguez - dribeas
 

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