octmode.md

x <- as.octmode(6:10)
x + 1
#> [1] "07" "10" "11" "12" "13"
x[NA_integer_]
#> [1] NA
as.octmode(NA)
#> Error in as.octmode(NA): 'x' cannot be coerced to class "octmode"
as.octmode(NA_integer_)
#> [1] NA

^{Created on 2021-04-06 by the reprex package (v1.0.0)}