From: Joel VanderWerf <vjoel@...>
Date: 2002-12-18T11:27:44+09:00
Subject: Re: named parameters

Greg Millam wrote:
> As for combining the two - having default values for hash arguments
> passed, that's quite a bit tricker. only way I can think of is
> 
> def foo(params)
>   params["baz"] = "Baz" unless params["baz"]
>   params["bar"] = "beer" unless params["bar"]
>   ...
> end
> 
> The problem with this method is, if a programmer wants to pass 'nil' or
> 'false' or any non-true value as an argument, the default values would
> overwrite that.

def foo(params)
   {:argA => "default A", :argB => "default B"}.update params
end

p foo(:argA=>nil)  # ==> {:argA=>nil, :argB=>"default B"}