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Indexing request

5 messages · David Winsemius, Duncan Murdoch, Brian Ripley

#
I just tried ?Constants at the console and was disappointed that the  
so-named base help page would not come up.

 > ?Constants
No documentation for 'Constants' in specified packages and libraries:
you could try '??Constants'

Seems like there should have been a match. I was looking for the month  
abbreviations, failing to hit the right name 4 times and then failing  
3 more times on variations of what I remembered to be the name of that  
page and finally ended up typing:

?letters

--

David Winsemius, MD
West Hartford, CT
#
On 11-01-07 12:08 AM, David Winsemius wrote:
I do see that page as the first hit if I follow the advice and type 
??Constants, though there seems to be a problem with the OSX help system 
and that particular page.

But I agree with you, and will add Constants to the index.

For future reference:  Every help page has:

  - a name (in this case "Constants"), which is what is displayed at the 
top of the help page.  It also determines the order in which pages are 
collated into the full manual, if you build one of those.
  - a title (which is a one-line explanation of the page); here it is 
"Built-in constants".  That is shown in the results from ??Constants.
  - a number of aliases, which are indexed.  Those are the things which 
work with a single ?.  In this case they are "LETTERS", "letters", 
"month.abb", "month.name", and "pi".
  - a filename (which you'll never see), in this case it's 
src/library/base/man/Constants.Rd.  That's the file to edit to make this 
change.

In most cases the name is repeated as an alias, but for some reason 
(flexibility?) that's not a requirement, and is not always the case, as 
here.  If I were designing the system I would say the name is 
automatically an alias, but perhaps there are cases where that would be 
undesirable.

I'll add it as an alias here.  I've passed on a message about the 
problem on that page, and it should eventually be fixed.

Duncan Murdoch
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On Fri, 7 Jan 2011, Duncan Murdoch wrote:

            
I am not so sure: Constants seems rather to be a \concept entry, and 
those are (deliberately) not searched by help()/?.  (There is also the 
question of capitalization: help() looks for exact matches.)
That was the case a decade ago, and it was found to be undesirable for 
various reasons (one was the restrictions on the value for \name, 
which used to be more severe than they are now).  Another was that 
where there were multiple matches the user was only offered one, so a 
badly chosen \name in a contributed package could mask completely an 
\alias in the standard system.

  
    
#
On 11-01-07 5:52 AM, Prof Brian Ripley wrote:
I think David's argument convinced me:  he had an imperfect memory of 
the page, but it included the name (which is displayed prominently when 
you see it).  Pages where the name is not an alias are so uncommon that 
most people don't realize that the name is not searched by help().
The help system can now handle duplicates, can't it?  Check will warn 
about duplicate aliases within a package, but alias conflicts across 
packages work fine.

Duncan
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On Fri, 7 Jan 2011, Duncan Murdoch wrote:

            
Yes, it now offers a menu of choices when there are multiple exact 
matches.  But AFAIR that was not the case when \name was removed as an 
automatic alias.