From: Joel VanderWerf <vjoel@...>
Date: 2004-11-05T14:47:53+09:00
Subject: Re: value provided for argument with default value - how to check inside method?

itsme213 wrote:
> Is there an equivalent of block_given? to check if the caller provided a
> value to an argument that had a default value?
> 
> Or do I have to use some sentinel value?

AFAIK, you either have to use

   def foo(*args)

and count args, or use hash arguments, which let you test with #key? :

   def foo(h={})
     if h.key?(:bar)
       puts "You passed :bar=>#{h[:bar]}"
     else
       h[:bar] = DEFAULT_BAR
     end
   end