`transmute()` accessing a new variable fails

[krlmlr]

library(tidyverse)
library(duckplyr)
#> ✔ Overwriting dplyr methods with duckplyr methods.
#> ℹ Turn off with `duckplyr::methods_restore()`.

data <-
  duckdb_tibble(
    g = c(1, 1, 2),
    a = 1:3,
    b = 2:4,
    c = 3:5,
    .prudence = "stingy"
  )

packed <-
  data |>
  transmute(g, d = a + b, e = d + c)
#> Error in `transmute()`:
#> ! This operation cannot be carried out by DuckDB, and the input is a
#>   stingy duckplyr frame.
#> ℹ Use `compute(prudence = "lavish")` to materialize to temporary storage and
#>   continue with duckplyr.
#> ℹ See `vignette("prudence")` for other options.
#> Caused by error:
#> ! object 'd' not found

^{Created on 2025-09-17 with reprex v2.1.1}

Works with mutate(.keep = "unused") .

[gmgui]

Hi Kirill,

Is the transmute() necessary?
Using mutate() with the option .keep = "none" worked for me.

library(duckplyr)
#> Loading required package: dplyr
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
#> ✔ Overwriting dplyr methods with duckplyr methods.
#> ℹ Turn off with `duckplyr::methods_restore()`.


data <- duckdb_tibble(
    g = c(1, 1, 2),
    a = 1:3,
    b = 2:4,
    c = 3:5,
    .prudence = "stingy"
  )

packed <- data |>
  mutate(d = a + b, e = d + c, .keep = "none")

packed
#> # A duckplyr data frame: 2 variables
#>       d     e
#>   <int> <int>
#> 1     3     6
#> 2     5     9
#> 3     7    12

^{Created on 2025-09-25 with reprex v2.1.1}