The only way as long as you commit to not look outside C++. There are plenty of text manipulation tools outside C++ that offer what could be done with the C++ preprocessor with programming paradigms that I consider unworthy of learning. Those tools (sed, awk, perl) are widely available, and in my humble opinion any programmer worth her salt should have at least a cursory understanding of them.
I've experimented with using PHP and C++ together, with good success. The nice thing about PHP is it lives inside my C++ source code, see a mini example [1] below. In the biggest real-world test of this I had a big PHP array of PHP objects, each object describing some algorithm. In my make file (actually scons) I compiled my "X.cpp.php" file into "X.cpp", which was then compiled by g++. Some issues I had: 1. I had to keep switching my editor between PHP syntax hilighting and C++ syntax. I could get around this by writing a syntax hilighter file for my editor. 2. I had to remember to edit the X.cpp.php file, not the X.cpp file. I got around this a bit by having scons make the X.cpp file read-only. 3. Line numbers of error messages. I guess they can all be summarized as lack of tool support. Darren [1] //Normal C++ code here <?php $types=Array('int','double','custom_type'); foreach($types as $t){ ?> <?php echo $t;?> generator_of_<?php echo $t;?>(int id){ //... <?php if($t)=='custom_type'){ ?> //Special code to make custom_type <?php }else{ ?> //Code to make built-in type <?php } ?> } //End of the generator_of_* functions <?php } ?> //More normal C++ code here