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3 messages · Phineas Campbell, Matthias Kohl

Phineas Campbell
# 
I'm creating a package for my own use that uses some S4 classes but no
methods.

I have a file called NAMESPACE it contains the line:

exportClasses("foo")

and at the top of the R file I have

setClass("foo", representation(x="numeric")

and the line:

.onLoad<-function(libname,pkgname)

When I run R CMD check I get Syntax error in the only R file.  If I comment
out the .onLoad function I get a package/namespace load failed error.

Are libname and pkgname parameters for the function .onLoad that need to
explicitly stated, or does R populate them when the package is loaded?

Does .onLoad as defined above do enough to ensure that the namesapce is
loaded?

Phineas Campbell
_
platform sparc-sun-solaris2.9
arch     sparc
os       solaris2.9
system   sparc, solaris2.9
status
major    2
minor    1.0
year     2005
month    04
day      18
language R
         _
Phineas Campbell
# 
Just noticed the mssing ) at the end of the setClass statement, it is there
in the orginal

Phineas

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of BBK
Sent: Thursday, December 08, 2005 8:18 PM
To: 'R-Help
Subject: [R] Loading namespaces


I'm creating a package for my own use that uses some S4 classes but no
methods.

I have a file called NAMESPACE it contains the line:

exportClasses("foo")

and at the top of the R file I have

setClass("foo", representation(x="numeric")

and the line:

.onLoad<-function(libname,pkgname)

When I run R CMD check I get Syntax error in the only R file.  If I comment
out the .onLoad function I get a package/namespace load failed error.

Are libname and pkgname parameters for the function .onLoad that need to
explicitly stated, or does R populate them when the package is loaded?

Does .onLoad as defined above do enough to ensure that the namesapce is
loaded?

Phineas Campbell
_
platform sparc-sun-solaris2.9
arch     sparc
os       solaris2.9
system   sparc, solaris2.9
status
major    2
minor    1.0
year     2005
month    04
day      18
language R
         _

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Matthias Kohl
# 
BBK schrieb:
Do you mean

.onLoad <- function(lib, pkg) require(methods)

as given in Section 1.6.6 of "Writing R Extensions"
see Section 1.6.6 (ibid.): "There needs to be an .onLoad action to
ensure that the methods package is loaded and attached"

hth
Matthias