Get old value in before_save or before_update using "_was'

Question

I am using Rails 2.3 and trying to have the submission date of a form changed only the first time that all required fields are filled.

Here's what I tried, both in before_save and before_update:

if ((self.required_fields_filled == true) and (self.required_fields_filled_was == false)) 
      self.submitted_at = Time.now
end

As long as required_fields_filled is currently true, it always updates submitted_at to Time.now

Any idea what I'm doing wrong?

Answer 1

This worked for me:

if (self.required_fields_filled == true)
      self.submitted_at ||= Time.now
end