From: Tom Sawyer <transami@...>
Date: 2002-08-08T19:36:53+09:00
Subject: Re: Named paramters again

did a little wondering about the internet, found this quote:

Viewing Hash and Array as instances of "Container" leads
to easy implementation of "Sparse Array" and "Sorted Hash"
and "Real Array" 

of course, what i'm suggesting is perhaps a bit more radical: unifying
array and hash --well, perhaps just making a new type of object which is
this unification (but given this, i can't exactly see why you'd still
need the other two, but no matter)

this new "MixedContainer" class could have a literal representation
denoted by parantheticals:

	( 'one', :opkey=>'two' )

then a subclass of Container could be made called Arguments, where
Arguments has some added features that give it some of the reminaing
applicaple characteristics of Ruby's current argument behavior, ie.
*array, &block and the like.

thus, calling any method simply boils down to passing a single Arguments
object.

	f ('one', :opkey=>'two')

which then could also be done like this:

	args = ('one', :opkey=>'two')
	f args

the end result? we get a new powerful class and named parameters in one
shot.

neat/clean/interestig idea?

~transami


p.s. found a nice pitch page for ruby:

  http://www.cse.unsw.edu.au/~gjmc469/



On Thu, 2002-08-08 at 04:05, Justin Johnson wrote:
> > Where this is used a lot in python are constructors in GUI widgets were
> > lots
> > of default values can be set and you only need to provide those you wish
> > to
> > 'override'...and yes...order independence becomes relevant here too
> > because you will have a hard time maintaining the order in your head for
> > 20 or 30 parameters.  Granted, you could just implement this as
> > subsequent calls to attribute getter/setters, but it's nice to be able
> > to do it in widget construction.
> 
> I see your point.
> 
> I think that the named argument method that I outlined serves a slightly
> different purpose to the one above.  The one I outlined gives the language a
> way of calling methods based on set named parameters in a way similar to
> Smalltalk and Objective-C.  The Python style call allows flexible
> specification of named arguments and seems particularly useful in the
> presence of default argument values.
> 
> The main thing for me is that the Python style named arguments must require
> extra processing when calling a method with named arguments.
> 
> But there again, maybe that's the price you pay for flexibility.
> 
> --
> Justin Johnson
> 
> 
> 
> 
-- 
~transami