The idea here is to capture three pieces of data: (1) a function for formatting digits in an output number (2) a default number of digits to use and (3) a named list with digit customization information; the names correspond to potential future column names and the values are custom digit information.
new_digits(.fun = sig, .default = 3, ..., .data = NULL)
x <- new_digits(round, .default = 2, WT = 1, ALB = 3)
as.list(x)
#> $has_digit_arg
#> [1] TRUE
#>
#> $arg
#> [1] "function (x, digits = 0, ...) "
#>