R devel - Feb 2007 - Writing a package in which files must be sourced in a specific order

Dear all,

I have been using the proto package to create objects with mutable
state for my ggplot package.  This has been very successful so far,
but I have run into a problem when building/installing the package,
because the source files need to be loaded in a specific order so that
dependencies are initialised correctly.

I have named the files so that dependencies are loaded before they are
needed, so that

lapply(dir("~/documents/ggplot/ggplot/R", full.name=T), source)

runs without error, but when installing the package I get an error
than indicates that the files aren't being loaded in alphabetical
order:

Error in proto(Geom, { : object "Geom" not found
Error: unable to load R code in package 'ggplot'
Error: package/namespace load failed for 'ggplot'

Can anyone suggest how I could get around this?

Regards,

Hadley

Put all loadings into functions and call the functions in .onLoad or 
.FirstLib, whatever you have there. I would simply advise not to put any 
  code outside of functions or class methods. In this way the order of 
loading will not matter, it will not depend on system or alphabet and 
you will also be able to save the loaded image of the package for faster 
loading.

Best
Oleg

hadley wickham wrote:
> Dear all,
> 
> I have been using the proto package to create objects with mutable
> state for my ggplot package.  This has been very successful so far,
> but I have run into a problem when building/installing the package,
> because the source files need to be loaded in a specific order so that
> dependencies are initialised correctly.
> 
> I have named the files so that dependencies are loaded before they are
> needed, so that
> 
> lapply(dir("~/documents/ggplot/ggplot/R", full.name=T), source)
> 
> runs without error, but when installing the package I get an error
> than indicates that the files aren't being loaded in alphabetical
> order:
> 
> Error in proto(Geom, { : object "Geom" not found
> Error: unable to load R code in package 'ggplot'
> Error: package/namespace load failed for 'ggplot'
> 
> Can anyone suggest how I could get around this?
> 
> Regards,
> 
> Hadley
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
-- 
Dr Oleg Sklyar | EBI-EMBL, Cambridge CB10 1SD, UK | +44-1223-494466

What 'alphabetical order' is depends on the locale.  In en_NZ g < G,
in C
G < g.  So it is a rather slippery concept (and gets worse in non-English 
locales: 'aa' sorts after z in Danish).

You don't tell us quite what you are doing, but R CMD INSTALL is 
working in C when concatenating the files in the R directory to ensure 
consistency across R installations.

My guess is that you need to give a collation order in the DESCRIPTION 
file (see 'Writing R Extensions'), if I am interpolating your 
comments correctly.

On Thu, 22 Feb 2007, hadley wickham wrote:
> Dear all,
>
> I have been using the proto package to create objects with mutable
> state for my ggplot package.  This has been very successful so far,
> but I have run into a problem when building/installing the package,
> because the source files need to be loaded in a specific order so that
> dependencies are initialised correctly.
'loaded'?  Do you mean sourced during INSTALL?
> I have named the files so that dependencies are loaded before they are
> needed, so that
>
> lapply(dir("~/documents/ggplot/ggplot/R", full.name=T), source)
>
> runs without error, but when installing the package I get an error
> than indicates that the files aren't being loaded in alphabetical
> order:
>
> Error in proto(Geom, { : object "Geom" not found
> Error: unable to load R code in package 'ggplot'
> Error: package/namespace load failed for 'ggplot'
>
> Can anyone suggest how I could get around this?
>
> Regards,
>
> Hadley
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595