Andrew B. wrote in post #1126301:
> The last line is equivalent to
> sum(42, 23) { |a, b| a + b }
>
> The & operator turns the operator referred to by the :+ symbol into a
> Proc.

This is interesting... I am trying to understand.. How should I catch 
such format for other cases..Here is some try :

def del a
  yield a,'c'
end
del 'abcd', &:delete
# => "abd"

While the above worked,why not the below ?

def del a
  yield a,'c','b'
end
del 'abcd', &:delete
# => "abcd"

-- 
Posted via http://www.ruby-forum.com/.