These function implement combination of lists or vectors of codes, while
preserving ICD classes. Base R c just drops all user defined classes
and casts down to lowest common denominator, e.g. if mixing numbers and
characters. No attempt here to catch all possible combinations of feeding in
mixed ICD types and other types. Let R do what it normally does, but just try
to keep classes of the first item in the list.
Usage
# S3 method for icd9
c(..., warn = FALSE)
# S3 method for icd10
c(..., warn = FALSE)
Arguments
...
elements to combine
warn
single logical value, if TRUE, will give warnings when
incompatible types are combined using c