Coding standards

• Try to divide the code in meaningful functions, write bricks not monoliths.
• When adding a feature think whether it can be a particular case of a more generic operation.
• Keep the functions as simple as possible. Instead of adding an option, think about what was forcing you to add that option (Doug McIlroy).
• When appropriate, try to follow the tidy tools manifesto.
• Use Hadley Wickham style guide; use snake_case variable naming.
• Write tests for all the features you add with the testthat package; test the package with R CMD check --as-cran.
• Document all your functions with the roxygen package. Use roxygen >= 0.6.0 syntax.
• Only export functions needed by the user. For simplicity of use keep the number of exported functions as low as possible. Consider using generics.
• Use S3 generics. Avoid S4.