Preprocess column for output

This is a generic function that applied to each column before it is saved to disk. It provides a hook for S3 classes that need special handling.

output_column(x)

Arguments

x	A vector

Examples

# Most columns are left as is, but POSIXct are
# converted to ISO8601.
x <- parse_datetime("2016-01-01")
str(output_column(x))
#>  chr "2016-01-01T00:00:00Z"