repro example does not work

[samlipworth]

library(data.table)
library(tidyverse)
library(dplyr)

mtcars2 <- lazy_dt(mtcars)
mtcars2 %>% 
  filter(wt < 5) %>% 
  mutate(l100k = 235.21 / mpg) %>% # liters / 100 km
  group_by(cyl) %>% 
  summarise(l100k = mean(l100k))

gives:
Error in env_get_list(ns_env("data.table"), dt_funs) :
argument "default" is missing, with no default

[samlipworth]

R version 4.0.2 (2020-06-22)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 18.04.4 LTS

Matrix products: default
BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.7.1
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.7.1

locale:
[1] LC_CTYPE=en_GB.UTF-8 LC_NUMERIC=C LC_TIME=en_GB.UTF-8 LC_COLLATE=en_GB.UTF-8 LC_MONETARY=en_GB.UTF-8 LC_MESSAGES=en_GB.UTF-8 LC_PAPER=en_GB.UTF-8 LC_NAME=C
[9] LC_ADDRESS=C LC_TELEPHONE=C LC_MEASUREMENT=en_GB.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] dtplyr_1.1.0 forcats_0.5.0 stringr_1.4.0 dplyr_1.0.5 purrr_0.3.4 readr_1.3.1 tidyr_1.1.0 tibble_3.0.3 ggplot2_3.3.2 tidyverse_1.3.0 data.table_1.12.8

loaded via a namespace (and not attached):
[1] Rcpp_1.0.5 cellranger_1.1.0 pillar_1.4.6 compiler_4.0.2 dbplyr_1.4.4 tools_4.0.2 jsonlite_1.7.0 lubridate_1.7.9.9001 lifecycle_1.0.0 gtable_0.3.0
[11] pkgconfig_2.0.3 rlang_0.4.10 reprex_0.3.0 cli_2.0.2 DBI_1.1.0 rstudioapi_0.11 haven_2.3.1 withr_2.2.0 xml2_1.3.2 httr_1.4.1
[21] fs_1.4.2 generics_0.0.2 vctrs_0.3.6 hms_0.5.3 grid_4.0.2 tidyselect_1.1.0 glue_1.4.1 R6_2.4.1 fansi_0.4.1 readxl_1.3.1
[31] modelr_0.1.8 blob_1.2.1 magrittr_1.5 backports_1.1.8 scales_1.1.1 ellipsis_0.3.1 parallelDist_0.2.4 rvest_0.3.5 assertthat_0.2.1 colorspace_1.4-2
[41] stringi_1.4.6 RcppParallel_5.0.2 munsell_0.5.0 broom_0.7.0 crayon_1.3.4

[myoung3]

I was able to reproduce this with data.table 1.12.8. For what it's worth, your code works starting in data.table 1.13.0 so upgrading data.table--if that's possible for your project--will fix this.

[myoung3]

traceback in 1.12.8:

> traceback()
9: env_get_list(ns_env("data.table"), dt_funs)
8: list3(...)
7: env_bind(env, !!!env_get_list(ns_env("data.table"), dt_funs))
6: add_dt_wrappers(env)
5: dt_eval(x)
4: as.data.table.dtplyr_step(x)
3: as.data.table(x)
2: print.dtplyr_step(x)
1: (function (x, ...)
   UseMethod("print"))(x)

[hadley]

We should add 1.13.0 as a minimum version in the DESCRIPTION

[markfairbanks]

@hadley - I just added the minimum version bump to the PR for expand()

[samlipworth]

great thanks both - does indeed work after data table update