I am just wondering what happened to the package swirl? It just gives me aborts my RStudio sessions whenever I chose some courses. For example, here I was loading the course Graphics Devices in R. However, it gave the following and it aborts my session
Graphics_Devices_in_R. (Slides for this and other Data Science courses may be found at github https://github.com/DataScienceSpecialization/courses/. If you care to use them, they must be downloaded as a zip file and viewed locally. This lesson corresponds to 04_ExploratoryAnalysis/Graphics_Devices_in_R.)
The error was here
Error in (function (srcref) : unimplemented type (29) in 'eval'