From philip at sctkjeld.dk  Tue Apr 21 23:47:50 2009
From: philip at sctkjeld.dk (Philip)
Date: Tue, 21 Apr 2009 23:47:50 +0200
Subject: [Rd] Sharing variables in seperate workspace
In-Reply-To: <6ph1vrmyvi4.fsf@gopher4.fhcrc.org>
References: <49ECFAEE.7020003@sctkjeld.dk> <6ph1vrmyvi4.fsf@gopher4.fhcrc.org>
Message-ID: <49EE3F06.2080208@sctkjeld.dk>

Hi Martin

Thank you very much. That solved my problem, and the package is now working!

Best regards. Philip.


Martin Morgan wrote:
> Philip <philip at sctkjeld.dk> writes:
> 
>> Hi all.
> 
> Hi Philip -- I think this thread
> 
>   https://stat.ethz.ch/pipermail/r-devel/2009-March/052867.html
> 
> addresses your issue. Basically, create an environment or closure in
> which you can modify variables.
> 
> HTH,
> 
> Martin
> 
>>
>> I'm for the first time trying to make a library in R 2.8.1 on Ubuntu
>> Linux. The library is very simple, R functions just need to share a
>> variable (that is defined in the R code) and maybe functions and export
>> functions for the user to .GlobalEnv. This variable should only be
>> directly accessible from the global workspace (without change of
>> environment) via a hereto dedicated function. It only consists of R
>> code. I'm not sure if I should rather ask R-help. If so, just tell me.
>>
>> The package source is available at
>> http://www.delff.dk/~philip/bdplot/
>> the check output at
>> http://www.delff.dk/~philip/bdplot.Rcheck/
>>
>> The package code was checked and stopped because of lack of examples.
>> Until that, everything is OK.
>>
>>> ### ** Examples
>>>
>>> ~~ simple examples of the most important functions ~~
>> Error: unexpected symbol in "~~ simple examples"
>> Execution halted
>>
>> I would like to get the code issue solved before moving the
>> documentation from the R scripts and have proceeded the to building and
>> installation. These two last steps gave no warnings or errors.
>>
>> My problem is that I cannot change the mentioned variable (from now on
>> called .FOO) that belongs to the namespace of the package. I think it is
>> because .FOO variable in some locked state, maybe by default created as
>> read-only. It is called .FOO because I use exportPattern("^[[:alpha:]]+")
>> as NAMESPACE file. I don't import anything.
>>
>> I have a function (bar) that, like par does with .Pars from the graphics
>> namespace, modifies the contents of a list. This function has in the
>> bottom (when the function name is called without () from the R command
>> line) a line
>>
>> <environment: namespace:"mypackage">
>>
>> This is like par() has the graphics namespace mentioned, and therefore,
>> as I would expect. I can via this function read the contents of the
>> variable just by print(.FOO). This cannot be done from .GlobalEnv which
>> is as intended. The surprise is that I cannot write to it. If I do
>>
>> .FOO$x <<- "value"
>> (names and values are arguments to the function, like with par().), I
>> get the error:
>>
>> cannot change value of locked binding for '.FOO'
>>
>> The double arrow, I use because <- does not affect the contents of .FOO
>> after the function has run. I don't know how I can use assign in this
>> case. I don't know a name for my package's environment. I have tried
>> with my package's name in both assign() and unlockBinding(), but my
>> package's name is not recognized as an environment (neither beginning
>> with a dot.). I also tryed unlockBinding() in the NAMESPACE file.
>>
>> I don't know if this is normal, but I get
>> <environment: R_GlobalEnv>
>> from print(parent.frame()) and things like
>> <environment: 0x8df2ad0>
>> from print(environment())
>> This is surprising to me. I would expect
>> <environment: bdplot>
>> from environment().
>>
>> How can I get to write to .FOO via bar()?
>>
>>
>> Thank you very much
>> Philip.
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>



[Rd] Sharing variables in seperate workspace
Philip