How to list all methods for an object in Ruby?
The following will list the methods that the User class has that the base Object class does not have...
>> User.methods - Object.methods
=> ["field_types", "maximum", "create!", "active_connections", "to_dropdown",
"content_columns", "su_pw?", "default_timezone", "encode_quoted_value",
"reloadable?", "update", "reset_sequence_name", "default_timezone=",
"validate_find_options", "find_on_conditions_without_deprecation",
"validates_size_of", "execute_simple_calculation", "attr_protected",
"reflections", "table_name_prefix", ...
Note that methods
is a method for Classes and for Class instances.
Here's the methods that my User class has that are not in the ActiveRecord base class:
>> User.methods - ActiveRecord::Base.methods
=> ["field_types", "su_pw?", "set_login_attr", "create_user_and_conf_user",
"original_table_name", "field_type", "authenticate", "set_default_order",
"id_name?", "id_name_column", "original_locking_column", "default_order",
"subclass_associations", ...
# I ran the statements in the console.
Note that the methods created as a result of the (many) has_many relationships defined in the User class are not in the results of the methods
call.
Added Note that :has_many does not add methods directly. Instead, the ActiveRecord machinery uses the Ruby method_missing
and responds_to
techniques to handle method calls on the fly. As a result, the methods are not listed in the methods
method result.
Or just User.methods(false)
to return only the methods defined within that class.