From: Brian Guthrie <btguthrie@...>
Date: 2007-04-30T14:31:59+09:00
Subject: Ways to change the behavior of a block

I'd like to be able to change the behavior of a call to a block (I'm
working on a design-by-contract system and would like to be able to
check the block's signature, filtering each call through some contract
check) and I was wondering if anyone had any advice.  It's easy enough
to override Proc#call, but doing so doesn't appear to affect calls to
implicit blocks with using the yield keyword.  Is it even possible to
do this?

Cheers,

Brian Guthrie