I'm trying to install a package using devtools as I've done many times before, but now I get the following error:
Error: JSON: EXPECTED value GOT <
In addition: Warning message:
In structure(xx, class = c("POSIXct", "POSIXt"), tzone = tz) :
Calling 'structure(NULL, *)' is deprecated, as NULL cannot have attributes.
Consider 'structure(list(), *)' instead.
It doesn't depend on the package I want to install, same error for different packages.
What does this error mean? and how can I fix it?
I'm using R Studio Version 1.1.463 and R 3.4.4.
> session_info() version R version 3.4.4 (2018-03-15) os Windows >= 8 x64 system x86_64, mingw32 ui RStudio language (EN) collate English_United Kingdom.1252 ctype English_United Kingdom.1252 tz Europe/Berlin date 2018-12-06 ](url)