From: Ryan Davis <ryand@...>
Date: 2002-09-20T18:35:36+09:00
Subject: RFC: Need a better caller(n) - real reflection for call stack wanted

RubyInline has the following extension to Object:

	def caller_method_name()
	  /\`([^\']+)\'/.match(caller(2).first)[1]
	end

Is there a better way???? caller(n) returns a string, and I have to 
parse it for the method name. This is scary at best. I'd much rather 
have something that gave me either the method instance itself, or some 
instance representation of the call stack. Something like:

	class CallStack

	  def line ... end			# returns the line of the calling method at this 
level (ATL)
	  def method ... end		# returns the calling method ATL
	  def class ... end		# returns the class for the calling method ATL
	  def to_s ... end			# equivalent output to the regular caller(n) 
method
	  def up ... end 			# returns a CallStack instance for one level up, 
or nil
	  def down ... end			# returns a CallStack instance for one level 
down, or nil

	end

and a method, callstack() that returns the current instance of 
CallStack. Or something like that. it would change my above method to:

	def caller_method_name()
	  callstack.up.up.method.name
	end

Which reads MUCH better, and you can manipulate a lot more with this 
type of expression.

I suppose up and down should also take int args like caller.

Now I'm tempted to go implement this... :) Just not sure how my ruby-fu 
in the internals are.