subtract documentation

[gevro]

Hi, subtract says that metadata columns of x are propagated, but that doesn't seem to be happening: "The names and metadata columns on x are propagated to the result."

> gr2 <- GRanges("a:1-10",score=10)
> gr1 <- GRanges("a:2-9")
> subtract(gr2,gr1)
GRangesList object of length 1:
[[1]]
GRanges object with 2 ranges and 0 metadata columns:
      seqnames    ranges strand
         <Rle> <IRanges>  <Rle>
  [1]        a         1      *
  [2]        a        10      *
  -------
  seqinfo: 1 sequence from an unspecified genome; no seqlengths

I think either the documentation is wrong, or subtract code is wrong.

Thanks