This function attempts to format numeric (or character) vectors
as character vectors of CAS numbers. If they cannot be converted to CAS
format or don't pass is.cas, NA is returned
Usage
as.cas(x, verbose = getOption("verbose"))
Value
character vector of valid CAS numbers
Arguments
x
numeric vector, or character vector of CAS numbers missing the
hyphens
verbose
logical; should a verbose output be printed on the console?