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    <p>The idea is coined "X-Macro". Some definitions won't include your particular example (X-macros generally are a bit more involved, with a file being included), but any relevant info. about this will fall under that term when searching.</p> <p>As <a href="https://stackoverflow.com/users/962089/chris">chris</a> mentioned in the comments, Boost.Preprocessor uses this idea to great effect. Popular uses are: <code>BOOST_PP_REPEAT</code>, <code>BOOST_PP_LIST_FOR_EACH</code>, and most powerfully: <code>BOOST_PP_ITERATE</code>.</p> <p><code>BOOST_PP_ITERATE</code> is a "true" X-Macro; including a single file is expands to something dependent on a macro defined just prior. I show a more "proper" skeleton framework in this <a href="https://stackoverflow.com/a/12963911/87234">other answer</a>, but an example would be:</p> <pre><code>// in xyz_data.def DEFINE_XYZ(foo, 1, "Description A") DEFINE_XYZ(bar, 5, "Description B") DEFINE_XYZ(baz, 7, "Description C") </code></pre> <p>Then later when I just want column 1 I can do:</p> <pre><code>#define DEFINE_XYZ(name, number, desc) some_func(name) #include "xyz_data.def" </code></pre> <p>And somewhere else where I want to generate some function for each one, I can do:</p> <pre><code>#define DEFINE_XYZ(name, number, desc) \ int BOOST_PP_CAT(get_number_for_, name)() \ { \ std::clog &lt;&lt; "Getting number, which is: " desc &lt;&lt; std::endl; \ \ return number; \ } #include "xyz_data.def" </code></pre> <p>You can then generate an enum where the name equals the number, etc.</p> <p>The power is that when I want to add a new xyz, I just add it in one spot and it magically shows up everywhere it needs to be. I have done something like this in a very large codebase to keep some bookmarking data in one central place, but the various attributes were used differently in various locations.</p> <p>Note that there is often no way around this; what I have are <em>syntactically different</em>, so no other language feature will generalize it for me to that level, only macros. Macros are not evil.</p> <p>What you have is effectively an X-macro where the .def file is self-contained enough to be a <code>#define</code>. In other words, <code>#include "xyz_data.def"</code> is just <code>TOP_LEVEL</code>.</p> <p>There is only one large downside to this, and ironically it's not the use of X-macros themselves but the effect they have on C and C++ compilers. The problem is that the preprocessor has allowed us to change the preprocessed result of a file every time its included, even if the file contents are <em>exactly the same</em>.</p> <p>You may have heard that C and C++ are slow to compile compared to modern languages, this is one of the reasons why. It has no proper module/packaging system, just ad-hoc inclusion of other files. And we just learned, <em>in general this cannot be avoided</em>. Oops. (That said, compilers are smart and will note when you have include guards around a file, for example, and avoid processing it multiple times. But this is situational.)</p> <p>That said, using X-Macros themselves shouldn't be a huge contributor to the compilation time of a real program. It's just that their mere potential existence reaches out into the real word and screws with compiler's heads.</p>
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    1. POFunctional-Programming Style in C++ Macros: Is this documented anywhere?
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    1. CORelies a bit too much on boost to overcome all the pitfalls for my gusto (not these aren't solved properly there). I still prefer using template metaprogramming and usage of variadic templates if necessary.
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    2. CO@g-makulik: You really can't conceive of a problem where a macro is the correct solution? Small box you live in.
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    3. COWithout getting into the pro/anti-macro debate (I'm too new to the language) I would say this is a thorough and informative answer to my question: thank you.
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