diff options
Diffstat (limited to 'lib/forwardable.rb')
| -rw-r--r-- | lib/forwardable.rb | 129 |
1 files changed, 111 insertions, 18 deletions
diff --git a/lib/forwardable.rb b/lib/forwardable.rb index a4af0217d0..59a760db45 100644 --- a/lib/forwardable.rb +++ b/lib/forwardable.rb @@ -70,9 +70,30 @@ # Ruby # nil # -# Forwardable can be used to setup delegation at the object level as well. +# SingleForwardable can be used to setup delegation at the object level as well. # # printer = String.new +# printer.extend SingleForwardable # prepare object for delegation +# printer.def_delegator "STDOUT", "puts" # add delegation for STDOUT.puts() +# printer.puts "Howdy!" +# +# Also, SingleForwardable can be use to Class or Module. +# +# module Facade +# extend SingleForwardable +# def_delegator :Implementation, :service +# +# class Implementation +# def service... +# end +# end +# +# If you want to use both Forwardable and SingleForwardable, you can +# use methods def_instance_delegator and def_single_delegator, etc. +# +# If the object isn't a Module and Class, You can too extend +# Forwardable module. +# printer = String.new # printer.extend Forwardable # prepare object for delegation # printer.def_delegator "STDOUT", "puts" # add delegation for STDOUT.puts() # printer.puts "Howdy!" @@ -111,8 +132,13 @@ # Also see the example at forwardable.rb. module Forwardable - FORWARDABLE_VERSION = "1.0.0" - + FORWARDABLE_VERSION = "1.1.0" + + @debug = nil + class<<self + attr_accessor :debug + end + # Takes a hash as its argument. The key is a symbol or an array of # symbols. These symbols correspond to method names. The value is # the accessor to which the methods will be delegated. @@ -121,7 +147,7 @@ module Forwardable # delegate method => accessor # delegate [method, method, ...] => accessor # - def delegate(hash) + def instance_delegate(hash) hash.each{ |methods, accessor| methods = methods.to_s unless methods.respond_to?(:each) methods.each{ |method| @@ -144,34 +170,101 @@ module Forwardable def def_instance_delegators(accessor, *methods) methods.delete("__send__") methods.delete("__id__") - methods.each{ |method| + for method in methods def_instance_delegator(accessor, method) - } + end end - # - # Defines a method _method_ which delegates to _obj_ (i.e. it calls - # the method of the same name in _obj_). If _new_name_ is - # provided, it is used as the name for the delegate method. - # def def_instance_delegator(accessor, method, ali = method) - str = %Q{ + line_no = __LINE__; str = %{ def #{ali}(*args, &block) - #{accessor}.send(:#{method}, *args, &block) + begin + #{accessor}.__send__(:#{method}, *args, &block) + rescue Exception + $@.delete_if{|s| %r"#{Regexp.quote(__FILE__)}"o =~ s} unless Forwardable::debug + ::Kernel::raise + end end } - # If it's not a class or module, it's an instance begin - module_eval(str) + module_eval(str, __FILE__, line_no) rescue - instance_eval(str) + instance_eval(str, __FILE__, line_no) end + end + alias delegate instance_delegate alias def_delegators def_instance_delegators alias def_delegator def_instance_delegator end -# compatibility -SingleForwardable = Forwardable +# +# Usage of The SingleForwardable is like Fowadable module. +# +module SingleForwardable + # Takes a hash as its argument. The key is a symbol or an array of + # symbols. These symbols correspond to method names. The value is + # the accessor to which the methods will be delegated. + # + # :call-seq: + # delegate method => accessor + # delegate [method, method, ...] => accessor + # + def single_delegate(hash) + hash.each{ |methods, accessor| + methods = methods.to_s unless methods.respond_to?(:each) + methods.each{ |method| + def_single_delegator(accessor, method) + } + } + end + + # + # Shortcut for defining multiple delegator methods, but with no + # provision for using a different name. The following two code + # samples have the same effect: + # + # def_delegators :@records, :size, :<<, :map + # + # def_delegator :@records, :size + # def_delegator :@records, :<< + # def_delegator :@records, :map + # + def def_single_delegators(accessor, *methods) + methods.delete("__send__") + methods.delete("__id__") + for method in methods + def_single_delegator(accessor, method) + end + end + + # + # Defines a method _method_ which delegates to _obj_ (i.e. it calls + # the method of the same name in _obj_). If _new_name_ is + # provided, it is used as the name for the delegate method. + # + def def_single_delegator(accessor, method, ali = method) + line_no = __LINE__; str = %{ + def #{ali}(*args, &block) + begin + #{accessor}.__send__(:#{method}, *args, &block) + rescue Exception + $@.delete_if{|s| %r"#{Regexp.quote(__FILE__)}"o =~ s} unless Forwardable::debug + ::Kernel::raise + end + end + } + + instance_eval(str, __FILE__, __LINE__) + end + + alias delegate single_delegate + alias def_delegators def_single_delegators + alias def_delegator def_single_delegator +end + + + + |