From: Kent Dahl <kentda@...>
Date: 2002-10-31T16:59:23+09:00
Subject: Re: Runtime access to the source code of a block?

Bulat Ziganshin wrote:
> i think you need method to COMPILE string into block, like:
> 
> block = compile("{|x| x*2}")
> p block.call(2)    #=>4

Doesn't eval suffice for this?

As for a potential hack for the OP, what about something like this:
class X
  def first_definition( &binding )
    @binding ||= binding
    source = binding.call
    redefine( source )
  end
  def redefine( source )
    @source = source
    @block = eval "Proc.new { #{source} }", @binding
  end
  def x(i)
    @block.call(i)
  end
end
x = X.new
a = 3
x.first_definition { %{|i|a+i} }
puts x.x(2) #=> 5
x.redefine %{|i|a-i}
puts x.x(2) #=> 1

# Ugly enough syntax to know that there is some bad mojo going on
atleast :-)


-- 
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