# respond\_to? / methods / method\_missing / instance\_methods (round 4)

**URL:** <https://discuss.rubyonrails.org/t/respond-to-methods-method-missing-instance-methods-round-4/37861>\
**Category:** rubyonrails-core\
**Created:** [January 1, 2009, 5:45pm UTC](https://discuss.rubyonrails.org/t/respond-to-methods-method-missing-instance-methods-round-4/37861 "2009-01-01T17:45:38Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Student](https://avatars.discourse-cdn.com/v4/letter/s/ecc23a/32.png) [@Student](https://discuss.rubyonrails.org/u/Student)\
**Post date:** [January 1, 2009, 5:45pm UTC](https://discuss.rubyonrails.org/t/respond-to-methods-method-missing-instance-methods-round-4/37861/1 "2009-01-01T17:45:38Z")

</div>

> > t = Test.new

=\> #\<Test id: nil, name: nil, created\_at: nil, updated\_at: nil\>

> > Test.public\_instance\_methods - ActiveRecord::Base.public\_instance\_methods

=\>

> > t.methods - ActiveRecord::Base.public\_instance\_methods

=\> ["updated\_at", "validate\_on\_update", "updated\_at=", "created\_at?", "name", "name=", "validate", "created\_at", "created\_at=", "name?", "validate\_on\_create", "updated\_at?"]

> > Test.public\_instance\_methods - ActiveRecord::Base.public\_instance\_methods

=\> ["updated\_at", "updated\_at=", "created\_at?", "name", "name=", "created\_at", "created\_at=", "name?", "updated\_at?"]

Test.public\_instance\_methods is not updated until t.methods has been called. This would appear to be in error.