Is SliceValue() a purely internal interface?

My use case is having parsed command line variables at start-of-day, I need to refer to them later.  I can use `pflags.Lookup()` to get a `Value` but this seems to only be able to return a string representation of the parameter's value.  My parameter happens to be a `[]string`  but I don't see how to read this unless I parse the string representation, which seems far from ideal.