The SingleForwardable module provides delegation of specified methods to a designated object, using the methods def_delegator and def_delegators. This module is similar to Forwardable, but it works on objects themselves, instead of their defining classes.
Also see the example at forwardable.rb.
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.
See the example at forwardable.rb.
# File forwardable.rb, line 199 def def_singleton_delegator(accessor, method, ali = method) accessor = accessor.id2name if accessor.kind_of?(Integer) method = method.id2name if method.kind_of?(Integer) ali = ali.id2name if ali.kind_of?(Integer) instance_eval(<<-EOS, "(__FORWARDABLE__)", 1) def #{ali}(*args, &block) begin #{accessor}.__send__(:#{method}, *args,&block) rescue Exception $@.delete_if{|s| /^\\(__FORWARDABLE__\\):/ =~ s} unless Forwardable::debug Kernel::raise end end EOS 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:
single_forwardable.def_delegators :@records, :size, :<<, :map single_forwardable.def_delegator :@records, :size single_forwardable.def_delegator :@records, :<< single_forwardable.def_delegator :@records, :map
See the example at forwardable.rb.
# File forwardable.rb, line 186 def def_singleton_delegators(accessor, *methods) for method in methods def_singleton_delegator(accessor, method) end end