From: ts <decoux@...>
Date: 2003-11-20T19:25:04+09:00
Subject: Re: "stereotyping" (was: Re: Strong Typing (Re: Managing metadata about attribute types) )

>>>>> "S" == Sean O'Dell <sean@celsoft.com> writes:

S> No, type checking based on class inheritance (and mix-ins) is completely
S> fine.   

 No, no, matz is right : it's bad

 Don't forget that I've written and *used* this

svg% cat b.rb
#!./ruby
class A
   def tt(Enumerable a)
      p "I respond to #each : #{a.inspect}"
   end

   def tt(Kernel a)
      p "I don't know #each : #{a.inspect}"
   end
end

a = A.new
a.tt([1, 2])
a.tt("string")
a.tt(A.new)

svg% 

svg% b.rb
"I respond to #each : [1, 2]"
"I respond to #each : \"string\""
"I don't know #each : #<A:0x4009c360>"
svg% 


Guy Decoux