Error(s) in re-building vignettes:
--- re-building ‘nCov2019.Rmd’ using rmarkdown
Quitting from lines 41-43 (nCov2019.Rmd) 
Error: processing vignette 'nCov2019.Rmd' failed with diagnostics:
object of type 'closure' is not subsettable
--- failed re-building ‘nCov2019.Rmd’

SUMMARY: processing the following file failed:
  ‘nCov2019.Rmd’

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
  ...
--- re-building ‘nCov2019.Rmd’ using rmarkdown
Quitting from lines 41-43 (nCov2019.Rmd) 
Error: processing vignette ‘nCov2019.Rmd’ failed with diagnostics:
parse error: premature EOF
                                       
                     (right here) ------^

--- failed re-building ‘nCov2019.Rmd’

SUMMARY: processing the following file failed:
  ‘nCov2019.Rmd’

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
  ...
--- re-building ‘nCov2019.Rmd’ using rmarkdown
Quitting from lines 41-43 (nCov2019.Rmd) 
Error: processing vignette ‘nCov2019.Rmd’ failed with diagnostics:
object of type ‘closure’ is not subsettable
--- failed re-building ‘nCov2019.Rmd’

SUMMARY: processing the following file failed:
  ‘nCov2019.Rmd’

Error: Vignette re-building failed.
Execution halted