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PONon-scalar type Sub-class error
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  1. PONon-scalar type Sub-class error
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    copied!<p>I must be living in a bizarro version of C++. In a section of my code I have:</p> <pre><code>TemplateIterator&lt;sf::Sound&gt; Temp; TemplateIteratorNonConst&lt;sf::Sound&gt; Temp2 = Temp; </code></pre> <p>Ignore the 'constness' naming conventions as TemplateIteratorNonConst is not presently any different from TemplateIterator. I get the error:</p> <pre><code>'TL::TemplateIterator&lt;sf::Sound&gt;' to non-scalar type 'TL::TemplateIteratorNonConst&lt;sf::Sound&gt;' requested </code></pre> <p>Which implies that C++ is having conversion issues. The mind-boggling fact is, TemplateIteratorNonConst is an empty sub-derivative, <em>an exact duplicate of TemplateIterator[1]</em>:</p> <pre><code>//Empty to demonstrate the absurdity of the error template&lt;typename TemplateItem&gt; class TemplateIteratorNonConst : public TemplateIterator&lt;TemplateItem&gt; { private: protected: public: }; </code></pre> <p>Even if I define the assignment operator (no matter which kind - TemplateIterator to NonConsts, vice versa, same for same etc), it makes no difference, it spits out the same error. It wouldn't be such a confusing error if it wasn't for the fact that:</p> <pre><code>TemplateIterator&lt;sf::Sound&gt; Temp; TemplateList&lt;sf::Sound&gt; Temp2 = Temp; //A sub-class of TemplateIterator </code></pre> <p>Produces absolutely no errors. Why is it, TemplateList, a sub-class of TemplateIterator, gets no 'non-scalar type' warnings in the exact same scenario, but TemplateIteratorNonConst, also a sub-class (and exact dupe) of TemplateIterator, does?</p> <p>I can't give a full code example due to length of both TemplateIterator and TemplateList on this page, and I've been unable to replicate the error with simple classes (exact duplicate sub-classes give no errors when performing assignment either way).</p> <p>Why is this error occuring, and <strong>without static type-casting</strong> (given TemplateList requires no type-casting to work and TemplateIteratorNonConst is a self-explanatory duplicate of TemplateIterator so it should not be necessary) how do I fix the problem?</p> <p>(I feel static type-casting is covering up a more major problem on the underneath so I'd much rather address it).</p> <p>[1]Okay, maybe not an 'exact' duplicate (it is a subclass of TemplatorIterator) for pedants but you know what I mean.</p>
 

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