Note the column name, mpg, is unquoted. That feature hasn’t been handy, though, if you want to write your own R functions using the tidyverse. That’s because base R functions usually need ...

See how the purrr package’s possibly() function helps you flag errors and keep going when applying a function over multiple objects in R.

Python, JavaScript & C++ examples - Void function, Functions in Programming that require or return a Value discussed in brief for beginners.