C++ Namespace Functions

I am a Java developer and I am pretty new to C++. I need to implement some kind of utility class, and I was thinking of implementing the methods as static. However, I came across to this stackoverflow question about namespace functions vs static method, and apprently namespace functions is preferred approach. So I would like to konw if there is any article or example on how to implement namespace function. E.g, how should I declare namespace functions in header file? Should header only contain function definitions like class header file and implementations should be in cpp file, or should I straight away implement functions in header file?

Basically, I am trying to implement an application to parse a text file that contains so commands. So I am thinking of implementing static helper methods to handle text processing. E.g readCommand(string line). Please let me know if I am in the wrong direction. Thanks

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