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    <h2>Yes! (well, sort of)</h2> <p>There are a couple publicly available tools to help you out. Both use preprocessor code generation to create templates which implement the custom operators. These operators consist of one or more built-in operators in conjunction with an identifier.</p> <p>Since these aren't actually custom operators, but merely tricks of operator overloading, there are a few caveats:</p> <ul> <li>Macros are evil. If you make a mistake, the compiler will be all but entirely useless for tracking down the problem.</li> <li>Even if you get the macro right, if there is an error in your usage of the operator or in the definition of your operation, the compiler will be only slightly more helpful.</li> <li>You must use a valid identifier as part of the operator. If you want a more symbol-like operator, you can use <code>_</code>, <code>o</code> or similarly simple alphanumerics.</li> </ul> <h3><a href="http://www.codeproject.com/KB/cpp/customoperators.aspx" rel="noreferrer">CustomOperators</a></h3> <p>While I was working on my own library for this purpose (see below) I came across this project. Here is an example of creating an <code>avg</code> operator:</p> <pre><code>#define avg BinaryOperatorDefinition(_op_avg, /) DeclareBinaryOperator(_op_avg) DeclareOperatorLeftType(_op_avg, /, double); inline double _op_avg(double l, double r) { return (l + r) / 2; } BindBinaryOperator(double, _op_avg, /, double, double) </code></pre> <h3><a href="http://cogwheel.info/idop/" rel="noreferrer">IdOp</a></h3> <p>What started as <a href="http://blog.cogwheel.info/2009/10/from-frivolity-functionality-follows.html" rel="noreferrer">an exercise in pure frivolity</a> became my own take on this problem. Here's a similar example:</p> <pre><code>template&lt;typename T&gt; class AvgOp { public: T operator()(const T&amp; left, const T&amp; right) { return (left + right) / 2; } }; IDOP_CREATE_LEFT_HANDED(&lt;, _avg_, &gt;, AvgOp) #define avg &lt;_avg_&gt; </code></pre> <p><H3>Key Differences</h3></p> <ul> <li>CustomOperators supports postfix unary operators</li> <li>IdOp templates use references rather than pointers to eliminate use of the free store, and to allow full compile-time evaluation of the operation</li> <li>IdOp allows you to easily specify several operations for the same root identifier</li> </ul>
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    1. POCan you make custom operators in C++?
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    1. COOne caveat: Since the pre-process stage happens before compilation, any error messages related to these custom operators have the potential to be VERY difficult to relate back to the code you wrote because the compile errors will be on whatever your code gets turned into. Not saying you shouldn't do it (if appropriate to your problem), but try to use sparingly - it's going to make your life difficult.
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      1. USMichael Kohne
    2. COSounds cool. Sounds clever. Something in the back of my head is telling me "You're doing it wrong" and "Custom operators were deliberately left out of the language spec."
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    3. CO@Michael Kohne: Absolutely agree. I had some maddening debugging experiences over the last couple days.
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