how to avoid check NOTE for ..variables in j? #4741

this is related to #2988
I put a line of code in R/fmelt.R

    other.values = lapply(group.dt[, ..is.other], unique)

and when I checked data.table I got

* checking R code for possible problems ... NOTE
measure: no visible binding for global variable ‘..is.other’
Undefined global functions or variables:
  ..is.other

so I tried the usual trick,

..is.other <- NULL

But that gave me this warning from R/data.table.R,

            warning("Both '",name,"' and '..", name, "' exist in calling scope. Please remove the '..", name,"' variable in calling scope for clarity.")

Eventually I removed the two dots altogether and instead used,

    other.values = lapply(group.dt[, is.other, with=FALSE], unique)

which works fine (no NOTE nor warning), but from the docs and #2826 it seems that with=FALSE will be deprecated in the future. If that is the case then how should R package developers who use ..something avoid that NOTE?