Clarify $ vs [, col] behavior in docs (#7369)#7381
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ben-schwen
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Oct 22, 2025
ben-schwen
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ben-schwen
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jangorecki
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Basically LGTM. Some wording sounds unusual and too eloborate for our usual style.
jangorecki
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Oct 22, 2025
| This means a variable created with `$` can change if the `data.table` is modified later, which can be unexpected. A single example demonstrates this behavior and how `copy()` provides a solution: | ||
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| ```{r} | ||
| library(data.table) |
Co-authored-by: Benjamin Schwendinger <52290390+ben-schwen@users.noreply.github.com>
Co-authored-by: Benjamin Schwendinger <52290390+ben-schwen@users.noreply.github.com>
Co-authored-by: Benjamin Schwendinger <52290390+ben-schwen@users.noreply.github.com>
Co-authored-by: Benjamin Schwendinger <52290390+ben-schwen@users.noreply.github.com>
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What about DT[["a"]] |
ben-schwen
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TY! |
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closes #7369
This PR clarifies the difference between DT$col and DT[, col] when selecting columns.
datatable-reference-semantics.Rmd:
Added a short section explaining that DT$col may return a reference, while DT[, col] always returns a copy. Included a minimal example.
datatable-faq.Rmd:
Added a brief note and link to the semantics vignette for details.
hi @jangorecki can you please review this when you have time ,and if any improvements are needed let me know .
thank you for your time.
thanks .