An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-devel/attachments/20100623/9038724f/attachment.pl>
format: different S4 behavior in a package
4 messages · Daniel Murphy, Uwe Ligges, Martin Morgan
There is not a single definition of formatMe() in your message, therefore nothing works for me, not even the very first version... Best, Uwe Ligges
On 23.06.2010 09:16, Daniel Murphy wrote:
R-Devel-ers:
I have an S4 method that simply formats an object:
setGeneric("formatMe", function(x) standardGeneric("formatMe"))
setMethod("formatMe", "ANY", function(x) format(x))
If I issue the above in an R session, then define an S4 class with its own
format method, I get the desired result:
setClass("A",contains="numeric")
[1] "A"
setMethod("format","A", function(x, ...) "Hey Jude")
Creating a new generic function for "format" in ".GlobalEnv" [1] "format"
a<-new("A",1968)
formatMe(a)
[1] "Hey Jude"
However, if I put the two "formatMe" definitions into a package ("Test"), I
do not get the desired result.
<start new R session>
library(Test)
setClass("A",contains="numeric")
[1] "A"
setMethod("format","A", function(x, ...) "Hey Jude")
Creating a new generic function for "format" in ".GlobalEnv" [1] "format"
a<-new("A",1968)
formatMe(a)
[1] "1968" The "disconnect" does not occur, however, if the S4 format method is an S3 incarnation:
setClass("B",contains="numeric",S3methods=TRUE)
[1] "B"
format.B<- function(x, ...) "Don't make it bad"
b<-new("B",1968)
formatMe(b)
[1] "Don't make it bad" Could the problem be in Test's NAMESPACE file? There is only one line: exportMethods(formatMe) Here is Test's DESCRIPTION file: Package: Test Type: Package Title: Testing format Version: 1.0 Date: 2010-06-22 Author: Dan Murphy Maintainer: Dan Murphy<snipped> Depends: methods Description: Does format in a package work with S4 format method? License: GPL (>= 2) LazyLoad: yes (I would send the Help file, but I don't think that is the problem.) I am using version 2.11.1 on a Windows Vista machine. Any guidance would be appreciated. Thank you Dan Murphy [[alternative HTML version deleted]]
______________________________________________ R-devel at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
On 06/23/2010 12:16 AM, Daniel Murphy wrote:
R-Devel-ers:
I have an S4 method that simply formats an object:
setGeneric("formatMe", function(x) standardGeneric("formatMe"))
setMethod("formatMe", "ANY", function(x) format(x))
If I issue the above in an R session, then define an S4 class with its own
format method, I get the desired result:
setClass("A",contains="numeric")
[1] "A"
setMethod("format","A", function(x, ...) "Hey Jude")
Creating a new generic function for "format" in ".GlobalEnv" [1] "format"
a<-new("A",1968)
formatMe(a)
[1] "Hey Jude"
However, if I put the two "formatMe" definitions into a package ("Test"), I
do not get the desired result.
<start new R session>
library(Test)
setClass("A",contains="numeric")
[1] "A"
setMethod("format","A", function(x, ...) "Hey Jude")
Creating a new generic function for "format" in ".GlobalEnv"
This is the clue -- you're creating a new S4 generic, so there's a base::format, and a .GlobalEnv::format. Test::formatMe respects its name space, and sees base::format. In the S3 case, base::format is already an S3 generic, and you're just adding a method, so there's only base::format for everyone to find. In Test, you could setGeneric(format) and then export(format). It might also be enough to just export(format); I'm not sure. Martin
[1] "format"
a<-new("A",1968)
formatMe(a)
[1] "1968" The "disconnect" does not occur, however, if the S4 format method is an S3 incarnation:
setClass("B",contains="numeric",S3methods=TRUE)
[1] "B"
format.B <- function(x, ...) "Don't make it bad"
b<-new("B",1968)
formatMe(b)
[1] "Don't make it bad" Could the problem be in Test's NAMESPACE file? There is only one line: exportMethods(formatMe) Here is Test's DESCRIPTION file: Package: Test Type: Package Title: Testing format Version: 1.0 Date: 2010-06-22 Author: Dan Murphy Maintainer: Dan Murphy <snipped> Depends: methods Description: Does format in a package work with S4 format method? License: GPL (>= 2) LazyLoad: yes (I would send the Help file, but I don't think that is the problem.) I am using version 2.11.1 on a Windows Vista machine. Any guidance would be appreciated. Thank you Dan Murphy [[alternative HTML version deleted]]
______________________________________________ R-devel at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Martin Morgan Computational Biology / Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N. PO Box 19024 Seattle, WA 98109 Location: Arnold Building M1 B861 Phone: (206) 667-2793
An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-devel/attachments/20100623/bfbae7f6/attachment.pl>