how to make a safely list output into a datatable

[jic007]

how to make a safely list output into a datatable
i am working with a function to copy files using fs::file_copy
The output using safely generates a list of lists containint file path error and status and it would be much easier to dignose issues if i get it in table format. Couldnt figur out how to do it

[brownj31]

@jic007 You can do that using enframe() and hoist().

items <- list('numbers' = 1:10, 'letters' = letters)

result <- 
  purrr::map(
    items, 
    purrr::safely(sum)
  )

result |>
  tibble::enframe() |>
  tidyr::hoist(value, 'result', 'error')
#> # A tibble: 2 x 3
#>   name    result error     
#>   <chr>    <int> <list>    
#> 1 numbers     55 <NULL>    
#> 2 letters     NA <smplErrr>

^{Created on 2023-04-24 with reprex v2.0.2}

[brownj31]

It does bother me that unnest_wider() doesn't work here. @hadley Is this a bug?

items <- list('numbers' = 1:10, 'letters' = letters)

result <- 
  purrr::map(
    items, 
    purrr::safely(sum)
  )

result |>
  tibble::enframe() |>
  tidyr::unnest_wider(value)
#> Error in `tidyr::unnest_wider()`:
#> i In column: `value`.
#> i In row: 2.
#> Caused by error in `list_sizes()`:
#> ! `x$error` must be a vector, not a <simpleError/error/condition> object.

#> Backtrace:
#>      x
#>   1. +-tidyr::unnest_wider(tibble::enframe(result), value)
#>   2. | \-tidyr:::col_to_wide(...)
#>   3. |   +-tidyr:::with_indexed_errors(...)
#>   4. |   | \-rlang::try_fetch(...)
#>   5. |   |   \-base::withCallingHandlers(...)
#>   6. |   \-purrr::map(...)
#>   7. |     \-purrr:::map_("list", .x, .f, ..., .progress = .progress)
#>   8. |       +-purrr:::with_indexed_errors(...)
#>   9. |       | \-base::withCallingHandlers(...)
#>  10. |       +-purrr:::call_with_cleanup(...)
#>  11. |       \-tidyr (local) .f(.x[[i]], ...)
#>  12. |         \-tidyr:::elt_to_wide(...)
#>  13. |           \-vctrs::list_sizes(x)
#>  14. \-vctrs:::stop_scalar_type(`<fn>`(`<smplErrr>`), "x$error", `<env>`)
#>  15.   \-vctrs:::stop_vctrs(...)
#>  16.     \-rlang::abort(message, class = c(class, "vctrs_error"), ..., call = vctrs_error_call(call))

^{Created on 2023-04-24 with reprex v2.0.2}

[hadley]

I don't think that's an unnest_wider() bug; it's just a artefact of the slightly different semantics that it has compared to hoist() (99% of the time those differences don't matter, but here they do).