R-assertthat

• If not done already, install MacPorts.
• To install R-assertthat, run the following command in macOS terminal (Applications->Utilities->Terminal)
  
  sudo port install R-assertthat Copy
• To see what files were installed by R-assertthat, run:
  
  port contents R-assertthat Copy
• To later upgrade R-assertthat, run:
  
  sudo port selfupdate && sudo port upgrade R-assertthat Copy

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