TinyExpr VS ExprTK

I had a hard time understanding your readme. I see that you use make to build the program; Why not compile? Does it read stdin or how do you use it? Is it a library you can include and use a command to evaluate arithmetic, like TinyExpr?

also read this codebase https://github.com/codeplea/tinyexpr

I have found many libraries that can evaluate mathematical expressions, e.g. this one: https://www.partow.net/programming/exprtk/index.html

I have used https://github.com/ArashPartow/exprtk for this task, since it is cpp we also used on IOS, however in android we changed to exp4j since it requires less space and did the same job.

For the specific example repo you cited, the project website also offers some preconfigured example MSVC solutions. You may find this much easier to get set up and running if using a Makefile is not a hard requirement.

This ExprTk library looks promising: https://www.partow.net/programming/exprtk/index.html

Now there are lots of libraries out there for expression processing as well. I would recommend exprtk: https://github.com/ArashPartow/exprtk

If your actual goal isn't to implement it yourself and you need it for something else, take a look at this library: https://github.com/ArashPartow/exprtk