[Rd] proposed changes to RSiteSearch

[Gabor Grothendieck]

On Thu, Jun 4, 2009 at 1:58 AM, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
> spencerg wrote:
>>
>> Hello All:
>>
>>      What do you think of adding a function "RSiteSeach" to the package of
>> that name, masking the "RSiteSearch" function in "utils", trapping any call
>> RSiteSearch('searchstring', 'function') to the current RSiteSearch.function
>> and passing all others to "utils:::RSiteSearch"?  This was suggested by a
>> referee to a manuscript on this new capability submitted to "R Journal".
>>  The current version of this manuscript is available via "system.file('doc',
>> 'RSiteSearch.pdf', package='RSiteSearch')" if you have the "RSiteSearch"
>> package installed.
>
> I suppose this depends on your long term plans for the function and package.
>  If you think it should eventually replace the utils function, then it makes
> sense to use the same name:  users won't get used to a new name in the
> meantime.  But if you think it will diverge from that function, then you
> might as well pick a separate name now.
>
> I disagree with Gabor about this being heavy handed, at least while it is
> the only significant export in the package.  If people don't want it, don't
> attach the package.
>

The last sentence only gives you a choice of clobbering the existing
function or not using it and that is not very nice.   What is wanted is
both to be able to use it and allow it to coexist in a nice way.

How about R changing its RSiteSearch to be an S3 generic with the
main functionality being placed into RSiteSearch.default?   Then
RSiteSearch.function can become RsiteSearch.character and

- RSiteSearch will give the new functionality when the package is
loaded and the old functionality if not.
- RSiteSearch.character can be used in place of RSiteSearch.function
to force only the new functionality (or an error if not present)
- RSiteSearch.default will give the old functionality whether or not the
package is loaded

(If there is a NAMESPACE then Its assumed here that both methods are
exported.)