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Regarding "Viewing TodoLists" Video's Scope Notes...

To be consistent with the hash-based method of scoping shouldn't the teacher notes for the "Viewing Todo Lists" video have had notes like the following used instead

class TodoItem < ActiveRecord::Base
  scope :incomplete, -> { where(completed_at: nil)}
  scope :complete, -> { where.not(completed_at: nil)}

  validates :content, presence: true, length: { minimum: 3 }
  belongs_to :todo_list

  def completed?


Where where.not is used to annotate a negation match?

1 Answer

Jason Seifer
Jason Seifer
Treehouse Guest Teacher

Hey Kevin Lozandier great comment! In a real application I could agree and go for consistency. This was done to show a couple of different ways of using scopes.