solved #4519 Need a reference page for .internal.selfref #6695
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Edit: in order to make the new help page more discoverable, find a few other appropriate help pages and link to internal.selfref from there. Either add it to the \seealso{...} section as \code{\link{internal.selfref}}, or add it directly to the main text as \link{internal.selfref} (optionally wrapped into \code{...}).
Are you the same person as @venom1204?
Edit: If yes, let's choose one out of the two pull requests for further review and close the other one. Avoiding unnecessary duplication of maintainers' work is the considerate thing to do.
| \alias{.internal.selfref} | ||
| \title{Internal Self-Reference Attribute in data.table} | ||
| \description{ | ||
| The `.internal.selfref` attribute is an internal mechanism used by \code{data.table} to optimize memory management and performance. This attribute ensures that \code{data.table} objects can be modified by reference without unnecessary copying, enabling efficient data manipulation. |
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Please don't use the ` backtick syntax ` in Rd files. The Rd syntax has \code for anything that can be parsed as valid R and \samp or \verb for other cases.
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yha @venom1204 is my account i am closing this pull request as @venom1204 will be my main account .
i will introduce all the necesarry changes and push them through @venom1204 account. @aitap
| The `.internal.selfref` attribute is a pointer that allows \code{data.table} objects to reference their own memory location. This avoids redundant memory allocation when performing in-place modifications such as adding or updating columns, filtering rows, or performing joins. | ||
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| If the `.internal.selfref` attribute is lost or corrupted (e.g., due to operations that inadvertently break reference semantics), \code{data.table} falls back to standard \code{data.frame}-like behavior, which can lead to reduced performance due to copying. | ||
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| Users generally do not need to interact directly with `.internal.selfref`, but understanding its purpose can help debug issues related to memory usage or unexpected copying in \code{data.table} operations. | ||
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| Note that `.internal.selfref` is automatically managed by \code{data.table} and is not intended to be modified by users. | ||
| } | ||
| \value{ | ||
| The `.internal.selfref` attribute is an internal implementation detail and does not produce a value that users would typically interact with. It is invisible during regular \code{data.table} operations. |
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Same thing about the backtick syntax here.
| dt[, C := A * 2] | ||
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| # Verify .internal.selfref is maintained | ||
| attr(dt, ".internal.selfref") |
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It's not very informative because the pointer fields always contains the address of R's NULL value.
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## master #6695 +/- ##
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Coverage 98.61% 98.61%
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Files 79 79
Lines 14559 14559
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Hits 14358 14358
Misses 201 201 ☔ View full report in Codecov by Sentry. |
closes #4519
i added a seperate file internal.selfref.rd
containing its
@MichaelChirico can you please review it.