Mauricio FernáÏdez <batsman.geo / yahoo.com> wrote in message 

> The point was that the "normal way" (with lambdas but not blocks la
> Ruby) would be
>   my_func(bar, baz, block) 
> ie. passing the lambda explicitly and having to use block.call inside
> my_func, instead of having yield call the "implicit block".
> 
> As for the creation of the block, that's by far the most common (and
> sensible) way, but what about (silly example)
> 
> irb(main):003:0> class A
> irb(main):004:1>   def foo(bar)
> irb(main):005:2>     puts "A#foo #{bar}"
> irb(main):006:2>   end
> irb(main):007:1> end
> => nil
> irb(main):008:0> block = A.instance_method(:foo).bind(A.new)
> => #<Method: A#foo>
> irb(main):009:0> 2.times &block
> (irb):9: warning: `&' interpreted as argument prefix
> A#foo 0
> A#foo 1
> => 2
> irb(main):010:0> block = A.new.method(:foo).to_proc
> => #<Proc:0x40189040@(irb):10>
> irb(main):011:0> 2.times &block
> (irb):11: warning: `&' interpreted as argument prefix
> A#foo 0
> A#foo 1
> => 2

Exactly what my question was intended to ask. So, it's been an
interesting discussion around blocks and yield, but any answer(s) to
the question:

What is the reason for the implicit block syntax?

And, along the way, any answers to my question (on a separate thread)
about why
   def ... end 
returns nil, instead of some kind of method object; and 
   class ... end
returns the last expression, also instead of some kind of class
instance.

Thanks.