Sha256: bf86b3848800384d280717a57d3a9ba33cd727423a1233275c48a96608d3081a
Contents?: true
Size: 1.85 KB
Versions: 35
Compression:
Stored size: 1.85 KB
Contents
module Perennial
# = Perennial::Hookable
#
# Perennial::Hookable provides a generic set of functionality
# for implementing simple block-based hooks / callbacks. On
# a class level, this makes it easy for you to do event driven
# programming in that code can be registered to be run
# when something happens.
#
# Hookable differs from Perennial::Dispatchable in that it is
# designed to be lightweight / used for things like setting things
# up without all of the overhead of defining handlers / dispatching
# messages.
module Hookable
def self.included(parent)
parent.class_eval do
extend ClassMethods
cattr_accessor :hooks
self.hooks = Hash.new { |h,k| h[k] = [] }
end
end
module ClassMethods
# Append a hook for a given type of hook in order
# to be called later on via invoke_hooks!
def append_hook(type, &blk)
self.hooks_for(type) << blk unless blk.blank?
end
# Return all of the existing hooks or an empty
# for a given hook type.
def hooks_for(type)
self.hooks[type.to_sym]
end
# Invoke (call) all of the hooks for a given
# type.
def invoke_hooks!(type)
hooks_for(type).each { |hook| hook.call }
end
# Defines a set of handy methods to make it
# easy to define simplistic block based hooks
# on an arbitrary class.
def define_hook(*args)
klass = self.metaclass
args.map { |a| a.to_sym }.each do |name|
klass.class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
def #{name}(&blk) # def before_run(&blk)
append_hook(:#{name}, &blk) # append_hook(:before_run, &blk)
end # end
RUBY
end
end
end
end
end
Version data entries
35 entries across 35 versions & 2 rubygems