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    <p>I would call such an append function by its name and would use operator+= , operator*= and so on for element-wise operations, such as:</p> <pre><code> template&lt;typename X&gt; inline void operator+= (std::vector&lt;X&gt;&amp; vec1, const X&amp; value) { std::transform( vec1.begin(), vec1.end(), vec1.begin(), std::bind2nd(std::plus&lt;X&gt;(),value) ); } template&lt;typename X&gt; inline void operator+= (std::vector&lt;X&gt;&amp; vec1, const std::vector&lt;X&gt;&amp; vec2) { std::transform( vec1.begin(), vec1.end(), vec2.begin(), vec1.begin(), std::plus&lt;X&gt;() ); } </code></pre> <p>some other simple and obvious wrappers as implied before:</p> <pre><code> template&lt;typename X&gt; inline void sort_and_unique(std::vector&lt;X&gt; &amp;vec) { std::sort( vec.begin(), vec.end() ); vec.erase( std::unique( vec.begin(), vec.end() ), vec.end() ); } template&lt;typename X&gt; inline void clear_vec(std::vector&lt;X&gt; &amp;vec) { std::vector&lt;X&gt;().swap(vec); } template&lt;typename X&gt; inline void trim_vec(std::vector&lt;X&gt; &amp;vec, std::size_t new_size) { if (new_size&lt;vec.size()) std::vector&lt;X&gt;(vec.begin(),vec.begin() + new_size).swap(vec); else std::vector&lt;X&gt;(vec).swap(vec); } </code></pre>
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    1. POWhich C++ Standard Library wrapper functions do you use?
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    1. USDane
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    1. COThese operators are a very good example why operator overloading should be done rarely. I would have thought, `vec+=val` would _append_ a value to the vector. (See http://stackoverflow.com/questions/2551775/.) Now that I have seen your implementation, I think this is just as right an interpretation of the meaning of `+=`, too. I wouldn't know which one would be right or wrong, so it's probably just as well that we don't have `+=` for `std::vector`.
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      1. USsbi
    2. CO@sbi I agree. I find `operator+()` missing an amazing early insight of the standard. I usually expect an O(1) operation everywhere I see the plus operator. C++ makes things that are expensive or dangerous more verbose or difficult to do, and I like it this way. Take a look at Java: one of the worst coding mistakes there is the abuse of the plus operator. Of course, then again, C++ doesn't always make cheap and fast things easy, but hey. Good C++ programmers are very much performance-aware. ;)
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      1. USwilhelmtell
    3. COI agree with both of you that `op+()` shouldn't be defined at all due to its ambiguity. But vectors are usually part of an (mathematical) vector space and there is a canonical definition of adding two vectors and scalar multiplication. To take your argument further: a simple `double` is a vector as well, so if you'd add two `double` variables like `a+b` then you'd expect to get a new `double` and not a `pair` of double like `(a,b)`. Multiplying with a scalar is canonical too, but multiplying two vectors is not. So overloading should be done with care..
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