romainfrancois commented on a change in pull request #8150:
URL: https://github.com/apache/arrow/pull/8150#discussion_r486283116
##########
File path: r/R/table.R
##########
@@ -185,6 +185,36 @@ Table <- R6Class("Table", inherit = ArrowObject,
)
)
+bad_attributes <- function(x) {
+ UseMethod("bad_attributes")
+}
+
+bad_attributes.default <- function(x) character()
+bad_attributes.data.frame <- function(x) c("class", "row.names", "names")
Review comment:
And if we do that, we get to reconstruct grouped data frames as well:
``` r
library(arrow, warn.conflicts = FALSE)
library(dplyr, warn.conflicts = FALSE)
df <- data.frame(x = 1:10, g = rep(1:2, each = 5)) %>% group_by(g)
as.data.frame(Table$create(df))
#> # A tibble: 10 x 2
#> # Groups: g [2]
#> x g
#> <int> <int>
#> 1 1 1
#> 2 2 1
#> 3 3 1
#> 4 4 1
#> 5 5 1
#> 6 6 2
#> 7 7 2
#> 8 8 2
#> 9 9 2
#> 10 10 2
```
<sup>Created on 2020-09-10 by the [reprex
package](https://reprex.tidyverse.org) (v0.3.0.9001)</sup>
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