The C++ preprocessor doesn’t understand anything about C++, including templates

&gt; The C and C++ preprocessors are like the Windows command prompt batch language: They implement a very simple language that people still use for some reason.<p>I can tell you exactly why I use batch scripts—they&#x27;re the only type of script that will run on double click in a stock Windows install.<p>Powershell scripts won&#x27;t by default for security reasons, but for some reason for batch it&#x27;s okay. So I use batch.

We&#x27;ve come across this problem. The major testing frameworks seem to rely heavily on macros for tests. In particular, we were struggling to handle tests of thrown exceptions, as we couldn&#x27;t trivially capture the result in a variable and place that inside the macro instead. The most versatile solution we found was to use a function pointer, so that the templating wasn&#x27;t required when the function was called.

The preprocessor is a really horrible hack of a macro system. I wish we could get rid of it and replace it with something sensible, but I doubt that will ever happen.

Just a PSA, but if the parenthesis solution doesn&#x27;t work for you, you can define a COMMA macro and use it there (while everyone yells at you).

Macros are inscrutable garbage and a sorry hack.