Uses parse_date_time
to transform string vectors with different date formats into
an R date vector, printed in ISO format.
If only the year is provided, then
the date will be set as June 30 of that year.
guessdate(messydate)Date in the format MM/DD/YYYY, MM/YYYY, or YYYY only.
Date vector in ISO date notation.
guessdate(c("03/28/2019", "03/2019", "03/19", "2019"))
#> [1] "2019-03-28" "2019-03-20" "2019-03-01" "2019-06-30"