I guess the error below should have been a warning, like the one indicated earlier.
library(lubridate)
#>
#> Attaching package: 'lubridate'
#> The following objects are masked from 'package:base':
#>
#> date, intersect, setdiff, union
parse_date_time("2020-11-12", orders = "md")
#> Warning: All formats failed to parse. No formats found.
#> [1] NA
parse_date_time("2020-11-12", orders = "yymd")
#> Warning in regexpr(reg, x, ignore.case = TRUE, perl = TRUE): PCRE pattern compilation error
#> 'two named subpatterns have the same name (PCRE2_DUPNAMES not set)'
#> at '\d{4})|(?<y>\d{2}))(?!\d)\D*?((?<Om>1[0-2]|0?[1-9](?!\d))|(((?<Om_b>Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)|(?<Om_B>January|February|March|April|May|June|July|August|September|October|November|December))(?![[:alpha:]])))\D*?(?<d>[012]?[1-9]|3[01]|[12]0)(?!\d))|(((?<Y_y_e>\d{4})|(?<y_e>\d{2}))\D*?((?<Y_y_e>\d{4})|(?<y_e>\d{2}))\D*?((?<Om_e>1[0-2]|0[1-9])|(((?<Om_b_e>Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)|(?<Om_B_e>January|February|March|April|May|June|July|August|September|October|November|December))(?![[:alpha:]])))\D*?(?<d_e>[012][1-9]|3[01]|[12]0)))\D*$'
#> Error in regexpr(reg, x, ignore.case = TRUE, perl = TRUE): invalid regular expression '^\D*?\b((((?<Y_y>\d{4})|(?<y>\d{2}))(?!\d)\D*?((?<Y_y>\d{4})|(?<y>\d{2}))(?!\d)\D*?((?<Om>1[0-2]|0?[1-9](?!\d))|(((?<Om_b>Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)|(?<Om_B>January|February|March|April|May|June|July|August|September|October|November|December))(?![[:alpha:]])))\D*?(?<d>[012]?[1-9]|3[01]|[12]0)(?!\d))|(((?<Y_y_e>\d{4})|(?<y_e>\d{2}))\D*?((?<Y_y_e>\d{4})|(?<y_e>\d{2}))\D*?((?<Om_e>1[0-2]|0[1-9])|(((?<Om_b_e>Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)|(?<Om_B_e>January|February|March|April|May|June|July|August|September|October|November|December))(?![[:alpha:]])))\D*?(?<d_e>[012][1-9]|3[01]|[12]0)))\D*$'
I guess the error below should have been a warning, like the one indicated earlier.
Created on 2023-10-15 with reprex v2.0.2