From: Robert Klemme <shortcutter@...>
Date: 2009-11-22T19:30:18+09:00
Subject: Re: Same name for class and instance method

On 22.11.2009 08:20, Ralph Shnelvar wrote:
> Newbie here.
> 
> Consider the following two "say" methods.
> 
> 
> irb(main):020:0> class Test2
> irb(main):021:1>   def self.say(block)
> irb(main):022:2>     block.call(self.class)
> irb(main):023:2>   end
> irb(main):024:1>   def say(block)
> irb(main):025:2>     block.call(self.class)
> irb(main):026:2>   end
> irb(main):027:1> end
> => nil
> irb(main):028:0> Test2.new.say(c)
> Test2
> => nil
> irb(main):029:0> Test2.say(c)
> Class
> 
> 
> (1) Do I have the nomenclature correct?  Are the two "say" methods a class
> and instance method?

Yes.

> (2) Is this valid Ruby both stylistically and semantically?

First of all, using the same name for a class and instance method can 
cause confusion, so it's probably not a too good idea in the general 
case.  That doesn't mean that there aren't valid use cases for this though.

The way you seem to be using a block (definition of c is missing in your 
example) is a bit unusual.  Usually you would do

def say
   yield self.class
end

or

def say(&block)
   block.call self.class
   # or shorter: block[self.class]
end

And invoke it like

Test2.say do |x|
   puts x
end

Again, it may make sense to invoke the method the way you did but the 
far more common idiom is the one I have shown.

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
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