cxxopts | Lightweight C++ command line option parser | Parser library

options.add_options() returns an object.

That object has the function call operator overload that takes two strings, which most likely looks like

It looks like a regex pattern, in which case the "++" likely needs some form of escaping. I'm not sure which form, because I don't know how the strings are being interpreted or what kind of regex syntax is being used, but some variant of the following should work:

My idea of letting gnumake do all processing proved to be wrong. The relevant differences between HP-UX 11i Version 1 and the latest Linux build are as follows:

• TAB before include was silently ignored; now it is interpreted as recipe prefix, and gnu make tries to find include executable on your machine.

• include in gnu make silently adds an empty line to the merged output resets the recipe on the boundary of each included file (as MadScientist correctly pointed out), thus included file cannot consist of recipe statements only.

If the included files don't use the same trick recursively (and in your example they seem to be plain actions, with no additional include statements), you can use awk to prepare the merged Makefile on the fly like this: