[Rd] Depot for S3 to S4 generics (as in stats4)?

Sven E. Templer sven.templer at gmail.com
Sun Jul 6 12:23:27 CEST 2014

Dear developers,

the implementation of S4 generics for existing S3 ones in the base
package is concerned to be a threat to quick startup times [1]. But
since S4 is promoted, and S3/S4 interoperability a pain when package
developing [2], are there efforts to improve the situation? E.g. an S3
free system, etc.

A good thing [2] is the package 'stats4', including some setGeneric
calls (e.g. for summary, plot, ...) which I can 'importFrom' to a
NAMESPACE. Nevertheless, functions as as.matrix, as. dist, merge,
duplicated, and for sure some others, are not available as S4
So my question is: will the base/graphics/... S3 generic definitions
for S4 methods be completely implemented in a future R release?
(E.g. in base4/stats4,/graphics4/... (by heritage [3]) or combined by
a single package such as genericS4)

Sorry I couldn't get more information from the devel archive (or find
a solution/answer) since the same idea already has been mentioned in
2007 [4]. Thank you for clarifying in advance.


[1] http://r.789695.n4.nabble.com/An-update-method-for-lists-td912749.html#a912756
[2] my opinion
[3] http://r.789695.n4.nabble.com/improved-error-message-when-existing-implicit-S4-generic-is-not-imported-td4421688.html#a4436278
[4] http://developer.r-project.org/BDR_S4issues.txt

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