The core of Bioconductor and the methods package itself once took
advantage of this "feature" to avoid unnecessary duplication. Since
the introduction of shallow copying, those abuses have been removed.
Note that these assignment functions always have issues due to
optimizations that assume <-()
It appears this started with R version 3.5.0. Under R 3.4.4 we have:
> setClass("Z", rep=representation(x="character"))
> z <- new("Z", x="orig")
> `@<-`(z, "x", value="newer")
An object of class "Z"
Slot "x":
[1] "newer"
> z
An object of class "Z"
Slot "x":
[1] "newer"
> `slot<-`(z, "x",
We noticed that the slot<- function alters its first argument, which goes
against the grain of a functional language. The similar @<- does not
change its first argument. Is this intended? The timeSeries and distr
package depend on this altering.
> setClass("Z",
