From: ara.t.howard@...
Date: 2006-11-30T08:10:17+09:00
Subject: Re: Wrong results using named arguments

On Thu, 30 Nov 2006, Jason  Vogel wrote:

> Okay, I have a couple of questions. If I use the Hash approach,
>
> - How do I handle argument default values?

   def the_method opts = { :arg => 'default value', :another_arg => 'default value too' }

> - How do I handle required vs. optional arguments?

   def the_method opts = { :a => 'default a', :b => 'default b', :c => nil }

     a = opts[:a] || opts['a']                  # optional, they pass in nil

     b = opts[:b] || opts['b'] or raise "no b!" # required


> - Provide some sort of clue to the calling routines what the argument
> "names" are?

   def the_method opts = { :arg => 'default value', :another_arg => 'default value too' }

> - Is there a way to enumerate the valid choices for values (e.g. colors
> = [red,white,blue])

   def the_method opts = { :a => %w( a b c ).first, :b => %w( d e f ).first }


-a
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