[R] Function call on every prompt

[Marc Schwartz]

On Nov 19, 2010, at 9:36 AM, Duncan Murdoch wrote:

> On 19/11/2010 10:31 AM, Marc Schwartz wrote:
>> On Nov 19, 2010, at 9:23 AM, Barry Rowlingson wrote:
>> 
>> >  Someone on stackoverflow.com was wondering how to display the current
>> >  time in the R prompt. I could have swore there was a mechanism for
>> >  hooking a function into R such that it is was called before the ">"
>> >  prompt was given, but no amount of searching in R's docs, R's source,
>> >  or RSiteSearch can find it.
>> >
>> >  I've searched for 'hook', 'event', 'signal', and various combinations
>> >  of those with 'console', 'prompt', 'after' and 'before' with no joy.
>> >  I'm sure other people have asked this on R-help before, but I can't
>> >  find those messages either.
>> >
>> >  Have I been hallucinating or is my search-fu week this Friday?
> 
> Barry was probably remembering SweaveHook.
> 
>> >
>> >  Barry
>> 
>> 
>> Baz,
>> 
>> What's wrong with:
>> 
>> >  options(prompt = paste(format(Sys.time(), "%a %b %d %X %Y %Z"), ">"))
>> Fri Nov 19 09:30:53 2010 CST>
>> Fri Nov 19 09:30:53 2010 CST>
>> Fri Nov 19 09:30:53 2010 CST>
> 
> That one doesn't get updated with every prompt.
> 
> Duncan Murdoch

D'oh....you are right.  Thanks Duncan....

Time for more coffee...

Marc