Reconsider dcdim default behaviour

[psolymos]

Array works fine:

r$> ## array
    x <- dcdim(array(1:6, c(2, 3, 1)))

r$> x1 <- dclone(x, 1)

r$> x2 <- dclone(x, 2)

r$> x
, , 1

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

attr(,"drop")
[1] TRUE
attr(,"class")
[1] "dcdim" "array"

r$> x1
, , 1

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

attr(,"drop")
[1] TRUE
attr(,"class")
[1] "dcdim" "array"

r$> x2
, , clone.1

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

, , clone.2

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

attr(,"n.clones")
[1] 2
attr(,"n.clones")attr(,"method")
[1] "dim"
attr(,"n.clones")attr(,"method")attr(,"drop")
[1] TRUE

r$> stopifnot(all(dim(x1) == dim(x)))

r$> stopifnot(all(dim(x2) == dim(x)*c(1,1,2)))

Should the matrix case add a 3rd dim when k=1?

r$> ## matrix
    x <- dcdim(matrix(1:6, 2, 3))

r$> x1 <- dclone(x, 1)

r$> x2 <- dclone(x, 2)

r$> x
     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6
attr(,"drop")
[1] TRUE
attr(,"class")
[1] "dcdim"  "matrix" "array" 

r$> x1
     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6
attr(,"drop")
[1] TRUE
attr(,"class")
[1] "dcdim"  "matrix" "array" 

r$> x2
, , clone.1

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

, , clone.2

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6

attr(,"n.clones")
[1] 2
attr(,"n.clones")attr(,"method")
[1] "dim"
attr(,"n.clones")attr(,"method")attr(,"drop")
[1] TRUE

r$> stopifnot(all(dim(x1) == dim(x)))

r$> stopifnot(all(dim(x2) == dim(x)*c(1,2)))
Error: all(dim(x2) == dim(x) * c(1, 2)) is not TRUE
In addition: Warning message:
In dim(x2) == dim(x) * c(1, 2) :
  longer object length is not a multiple of shorter object length