Contents

# $Id: future.rb 668 2008-01-04 23:00:34Z blackhedd $
#
# Author:: Francis Cianfrocca (gmail: blackhedd)
# Homepage::  http://rubyeventmachine.com
# Date:: 16 Jul 2006
# 
# See EventMachine and EventMachine::Connection for documentation and
# usage examples.
#
#----------------------------------------------------------------------------
#
# Copyright (C) 2006-07 by Francis Cianfrocca. All Rights Reserved.
# Gmail: blackhedd
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of either: 1) the GNU General Public License
# as published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version; or 2) Ruby's License.
# 
# See the file COPYING for complete licensing information.
#
#---------------------------------------------------------------------------
#
# 

# This defines EventMachine::Deferrable#future, which requires
# that the rest of EventMachine::Deferrable has already been seen.
# (It's in deferrable.rb.)
#
# A future is a sugaring of a typical deferrable usage.

module EventMachine
    module Deferrable

	class << self
	    # Evaluate arg (which may be an expression or a block).
	    # What's the class of arg?
	    # If arg is an ordinary expression, then return it.
	    # If arg is deferrable (responds to :set_deferred_status),
	    # then look at the arguments. If either callback or errback
	    # are defined, then use them. If neither are defined, then
	    # use the supplied block (if any) as the callback.
	    # Then return arg.
	    def future arg, cb=nil, eb=nil, &blk
		arg = arg.call if arg.respond_to?(:call)

		if arg.respond_to?(:set_deferred_status)
		    if cb || eb
			arg.callback(&cb) if cb
			arg.errback(&eb) if eb
		    else
			arg.callback(&blk) if blk
		    end
		end

		arg
	    end
	end

    end
end

Version data entries

3 entries across 3 versions & 1 rubygems

Version	Path
eventmachine-0.12.0-i386-mswin32	lib/em/future.rb
eventmachine-0.12.0	lib/em/future.rb
eventmachine-0.12.2	lib/em/future.rb