Question

I want to create a class that has one method that calls all other methods that are not in the super class.

Is there a way I can use obj.methods to only get the non-ancestral methods? Or is there another way to do it entirely.

Thank you

Answer 1

I’m not sure what you’re really trying to do here, nor which methods you mean by ‘all’, but if the question is how you figure out which of a class’s instance methods aren’t inherited, the combination of .instance_methods and .ancestors can get you that info. Here, using Array as an example class:

Array.instance_methods.sort                                                                          => ['&', '*', '+', '-', '<<', '<=>', '==', '===', '=~', '[]', '[]=', '__id__', '__send__', 'all?', 'any?', 'assoc', 'at', 'class', 'clear', 'clone', 'collect', 'collect!', 'compact', 'compact!', 'concat', 'delete', 'delete_at', 'delete_if', 'detect', 'display', 'dup', 'each', 'each_index', 'each_with_index', 'empty?', 'entries', 'eql?', 'equal?', 'extend', 'fetch', 'fill', 'find', 'find_all', 'first', 'flatten', 'flatten!', 'freeze', 'frozen?', 'grep', 'hash', 'id', 'include?', 'index', 'indexes', 'indices', 'inject', 'insert', 'inspect', 'instance_eval', 'instance_of?', 'instance_variable_get', 'instance_variable_set', 'instance_variables', 'is_a?', 'join', 'kind_of?', 'last', 'length', 'map', 'map!', 'max', 'member?', 'method', 'methods', 'min', 'nil?', 'nitems', 'object_id', 'pack', 'partition', 'pop', 'private_methods', 'protected_methods', 'public_methods', 'push', 'rassoc', 'reject', 'reject!', 'replace', 'respond_to?', 'reverse', 'reverse!', 'reverse_each', 'rindex', 'select', 'send', 'shift', 'singleton_methods', 'size', 'slice', 'slice!', 'sort', 'sort!', 'sort_by', 'taint', 'tainted?', 'to_a', 'to_ary', 'to_s', 'transpose', 'type', 'uniq', 'uniq!', 'unshift', 'untaint', 'values_at', 'zip', '|']  Array.ancestors => [Array, Enumerable, Object, Kernel]  Array.instance_methods.sort - Array.ancestors.map {|a| a == Array ? [] : a.instance_methods}.flatten => ['&', '*', '+', '-', '<<', '<=>', '[]', '[]=', 'assoc', 'at', 'clear', 'collect!', 'compact', 'compact!', 'concat', 'delete', 'delete_at', 'delete_if', 'each', 'each_index', 'empty?', 'fetch', 'fill', 'first', 'flatten', 'flatten!', 'index', 'indexes', 'indices', 'insert', 'join', 'last', 'length', 'map!', 'nitems', 'pack', 'pop', 'push', 'rassoc', 'reject!', 'replace', 'reverse', 'reverse!', 'reverse_each', 'rindex', 'shift', 'size', 'slice', 'slice!', 'sort!', 'to_ary', 'transpose', 'uniq', 'uniq!', 'unshift', 'values_at', '|'] 

If you literally only want to rule out methods from the superclass, as opposed to the included ones, there’s also .superclass.

Array.superclass => Object  Array.instance_methods.sort - Array.superclass.instance_methods => ['&', '*', '+', '-', '<<', '<=>', '[]', '[]=', 'all?', 'any?', 'assoc', 'at', 'clear', 'collect', 'collect!', 'compact', 'compact!', 'concat', 'delete', 'delete_at', 'delete_if', 'detect', 'each', 'each_index', 'each_with_index', 'empty?', 'entries', 'fetch', 'fill', 'find', 'find_all', 'first', 'flatten', 'flatten!', 'grep', 'include?', 'index', 'indexes', 'indices', 'inject', 'insert', 'join', 'last', 'length', 'map', 'map!', 'max', 'member?', 'min', 'nitems', 'pack', 'partition', 'pop', 'push', 'rassoc', 'reject', 'reject!', 'replace', 'reverse', 'reverse!', 'reverse_each', 'rindex', 'select', 'shift', 'size', 'slice', 'slice!', 'sort', 'sort!', 'sort_by', 'to_ary', 'transpose', 'uniq', 'uniq!', 'unshift', 'values_at', 'zip', '|'] 

Does that help?