From: Joel VanderWerf <vjoel@...>
Date: 2006-11-30T16:29:06+09:00
Subject: Re: Wrong results using named arguments

Joel VanderWerf wrote:
> ara.t.howard@noaa.gov wrote:
>> 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' }
> 
> Not really, at least in 1.8. That sets the default for _opts_, not for 
> each of the named args.

This is one way to handle defaults for keyword args:

DEFAULTS = {
   :x => 1,
   :y => 2
}

def m opts = {}
   opts = DEFAULTS.merge(opts)
   p opts
end

m :x => 5  # ==> {:x=>5, :y=>2}

Note that #merge is non-destructive (unlike #update, aka #merge!), so it 
doesn't affect DEFAULTS.

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407