Re: need obsolete arg in (read-from-minibuffer ...)

[ken <gebser@mousecar.com>]

On 03/18/2011 07:03 PM Drew Adams wrote:
>>> What do you mean by "work"?  And what do you mean "without" 
>>> the obsolete arg?
>> If I change the 2nd arg from "def-val" to "nil", then def-val
>> isn't displayed in the minibuffer for editing by the user.
>> However, the docs say that this arg is obsolete.
>> I take this to mean that it should be left as "nil".
> 
> Correct.  By "obsolete" the docs mean that that the Emacs developers think you
> should leave it as nil (i.e., not use the INITIAL-CONTENTS argument), and use
> only the DEFAULT-VALUE argument.
> 
> They think that the only useful use cases make no use of INITIAL-CONTENTS.  But
> see the doc string wrt the HIST arg, where they allow for an exception.
> 
> However, if you understand the difference between DEFAULT-VALUE and
> INITIAL-CONTENTS, and _you prefer_ the behavior of INITIAL-CONTENTS for some
> reason in some particular context, then use it.  Personally, I do not consider
> INITIAL-CONTENTS obsolete, FWIW.
> 
> Remember that you can pull the DEFAULT-VALUE into the minibuffer using `M-n'.
> So the difference typically comes down to which you find more convenient: having
> a value in the minibuffer initially (and having to get rid of it if you really
> want something else instead) or pulling a value into the minibuffer when you
> need it, using `M-n'.
> 
> If the default/initial value is used most of the time, then you might find it
> more convenient to have the minibuffer prefilled with it.  If it is not used
> most of the time then you might find it more convenient not to have to clear it
> out of the minibuffer and type another value.  And this relative convenience
> might change, depending on the command and the context.
> 
> ....

Really?  This is why that 2nd arg was declared obsolete!?  That's rather
goofy.  I thought there was some technical reason for it-- something to
do with code.  Oh well....  Thanks for the answer.