calling data.table functions when developing a package

Question

I'm developing a package that uses data.table, but when I call certain data.table functions, such as DT[, ..colnames] or DT[grepl("foo", col)] or DT[, .(colname)] I get errors like: "colnames not found" or "could not find function "."". These errors are being called from data.frame so I guess when R looks for the functions, it's looking for them inside data.frame instead of data.table. When I run class(DT), I get "data.table" "data.frame"

I also tried DT[, data.table::.(colname)] but get the error that '.' is not an exported object from namespace:data.table.

I haven't run into this behavior outside of the context of package development. Can someone provide me with some advice?

Old answer but can be helpful https://stackoverflow.com/questions/10527072/using-data-table-package-inside-my-own-package — Ronak Shah, Jul 20 '23 at 12:22
Does your package import data.table (in DESCRIPTION and NAMESPACE)? — Roland, Jul 20 '23 at 12:23
I had import data.table in DESCRIPTION but not in NAMESPACE. This was the issue, thank you — asahi, Jul 20 '23 at 16:20

asahi · Answer 1 · 2023-07-20T16:27:44.113

0

Per the comments, the solution was to import data.table in both DESCRIPTION and NAMESPACE. I also found this vignette to be helpful - https://cran.r-project.org/web/packages/data.table/vignettes/datatable-importing.html

This resource was also helpful: https://r-pkgs.org/dependencies-mindset-background.html#sec-dependencies-NAMESPACE-file

edited Jul 20 '23 at 16:27

answered Jul 20 '23 at 16:21

asahi

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calling data.table functions when developing a package

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