[Rd] declaring package dependencies

[Michael Friendly]

I received the following email note re: the vcdExtra package

> A vcd update has shown that packages TIMP and vcdExtra are not 
> declaring their dependence on colorspace/MASS: see
>
> http://cran.r-project.org/web/checks/check_results_vcdExtra.html
But, I can't see what to do to avoid this, nor understand what has 
changed in R devel.

Sure enough, CRAN now reports errors in examples using MASS::loglm(), 
using R Under development (unstable) (2013-09-11 r63906)

 > Caesar.mod0 <- loglm(~Infection + (Risk*Antibiotics*Planned), 
data=Caesar)
Error: could not find function "loglm"

In DESCRIPTION I have
Depends: R (>= 2.10), vcd, gnm (>= 1.0.3)
Suggests: 
ca,gmodels,Fahrmeir,effects,VGAM,plyr,rgl,lmtest,MASS,nnet,ggplot2,Sleuth2,car

and the vcd DESCRIPTION has

Depends: R (>= 2.4.0), grid, stats
Suggests: KernSmooth, mvtnorm, kernlab, HSAUR, coin
Imports: utils, MASS, grDevices, colorspace

so, in an R 3.0.0 console, library(vcdExtra) loads vcd and its dependencies:

 > library(vcdExtra)
Loading required package: vcd
Loading required package: MASS
Loading required package: grid
Loading required package: colorspace
Loading required package: gnm
Warning messages:
1: package ‘vcd’ was built under R version 3.0.1
2: package ‘MASS’ was built under R version 3.0.1
 >

Note: these CRAN errors do not occur on R-Forge, using R version 3.0.1 
Patched (2013-08-21 r63645)
and the latest devel version (0.5-11) of vcdExtra.

-Michael

-- 
Michael Friendly     Email: friendly AT yorku DOT ca
Professor, Psychology Dept. & Chair, Quantitative Methods
York University      Voice: 416 736-2100 x66249 Fax: 416 736-5814
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