Install gpp by entering the following commands in the terminal:
sudo apt update sudo apt install gpp
Description:
A general-purpose preprocessor with customizable syntax
GPP is a general-purpose preprocessor with customizable syntax, suitable for a wide range of preprocessing tasks. Its independence from any one programming language makes it much more versatile than the C preprocessor (cpp), while its syntax is lighter and more flexible than that of GNU m4. There are built-in macros for use with C/C++, LaTeX, HTML, XHTML, and Prolog files.
Homepage: http://www.nothingisreal.com/gpp/
Version: 2.24-3build1
Section: universe/devel