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    <p>Solution: When coding a comparison, have the return type be a <code>comparison</code> object that can chain additional comparisons, but is implicitly convertible to a <code>bool</code>. This can even (kind of) work with types that weren't coded with this intent, simply by casting them to the <code>comparison</code> type manually.</p> <p>Implementation:</p> <pre><code>template&lt;class T&gt; class comparison { const bool result; const T&amp; last; public: comparison(const T&amp; l, bool r=true) :result(r), last(l) {} operator bool() const {return result;} comparison operator&lt;(const T&amp; rhs) const {return comparison(rhs, (result &amp;&amp; last&lt;rhs));} comparison operator&lt;=(const T&amp; rhs) const {return comparison(rhs, (result &amp;&amp; last&lt;=rhs));} comparison operator&gt;(const T&amp; rhs) const {return comparison(rhs, (result &amp;&amp; last&gt;rhs));} comparison operator&gt;=(const T&amp; rhs) const {return comparison(rhs, (result &amp;&amp; last&gt;=rhs));} }; </code></pre> <p>A useful example:</p> <pre><code>#include &lt;iostream&gt; int main() { //testing of chained comparisons with int std::cout &lt;&lt; (comparison&lt;int&gt;(0) &lt; 1 &lt; 2) &lt;&lt; '\n'; std::cout &lt;&lt; (comparison&lt;int&gt;(0) &lt; 1 &gt; 2) &lt;&lt; '\n'; std::cout &lt;&lt; (comparison&lt;int&gt;(0) &gt; 1 &lt; 2) &lt;&lt; '\n'; std::cout &lt;&lt; (comparison&lt;int&gt;(0) &gt; 1 &gt; 2) &lt;&lt; '\n'; } </code></pre> <p>Output:</p> <pre><code>1 0 0 0 </code></pre> <p>Note: This was created by <a href="https://stackoverflow.com/users/845092/mooing-duck">Mooing Duck</a>, and a compiled, more robust example can be found on <a href="http://ideone.com/awrmK" rel="nofollow noreferrer">http://ideone.com/awrmK</a></p>
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    1. CONow that you've answered "can it be done?", "should it be done?" is left as an exercise for the reader.
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