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POWhat are good use-cases for tuples in C++11?
 

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  1. POWhat are good use-cases for tuples in C++11?
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    <p>What are good use-cases for using tuples in C++11? For example, I have a function that defines a local struct as follows:</p> <pre><code>template&lt;typename T, typename CmpF, typename LessF&gt; void mwquicksort(T *pT, int nitem, const int M, CmpF cmp, LessF less) { struct SI { int l, r, w; SI() {} SI(int _l, int _r, int _w) : l(_l), r(_r), w(_w) {} } stack[40]; // etc </code></pre> <p>I was considering to replace the <code>SI</code> struct with an <code>std::tuple&lt;int,int,int&gt;</code>, which is a far shorter declaration with convenient constructors and operators already predefined, but with the following disadvantages:</p> <ul> <li>Tuple elements are hidden in obscure, implementation-defined structs. Even though Visual studio interprets and shows their contents nicely, I still can't put conditional breakpoints that depend on value of tuple elements.</li> <li>Accessing individual tuple fields (<code>get&lt;0&gt;(some_tuple)</code>) is far more verbose than accessing struct elements (<code>s.l</code>).</li> <li>Accessing fields by name is far more informative (and shorter!) than by numeric index.</li> </ul> <p>The last two points are somewhat addressed by the <code>tie</code> function. Given these disadvantages, what would be a good use-case for tuples?</p> <p><strong>UPDATE</strong> Turns out that VS2010 SP1 debugger cannot show the contents of the following array <code>std::tuple&lt;int, int, int&gt; stack[40]</code>, but it works fine when it's coded with a struct. So the decision is basically a no-brainer: if you'll ever have to inspect its values, use a struct [esp. important with debuggers like GDB].</p>
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    1. COthe indexing problem can be solved with proper defined consts/enums.
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    2. COYou wrote a sort function that takes `T*, size`? lolwot, why would you ever do such a thing.
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    3. CO@DeadMG Just so that I can give you some material for trolling.
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