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Ruby Ruby Modules Store Inventory Using Modules Stock Counts

kabir k
PLUS
kabir k
Courses Plus Student 18,036 Points
Posted by kabir k
kabir k
Courses Plus Student 18,036 Points

The @ symbol in the Inventoryable module

In the Inventoryable module, why are we using the @ symbol in the first two methods and not in the last one?

module Inventoryable

  def stock_count
    @stock_count ||= 0
  end

  def stock_count=(number)
    @stock_count = number
  end

  def in_stock?
    stock_count > 0
  end

end

1 Answer

Milo Winningham
seal-mask
.a{fill-rule:evenodd;}techdegree
Milo Winningham
Web Development Techdegree Student 3,317 Points
Milo Winningham
.a{fill-rule:evenodd;}techdegree
Milo Winningham
Web Development Techdegree Student 3,317 Points

The first two methods access the @stock_count instance variable directly. The last method uses the stock_count method, which initializes @stock_count to 0 if it doesn't have a value. If the in_stock? method accessed @stock_count directly, the comparison would fail if the stock count had never been set.

Jesse vB
Jesse vB
16,959 Points

Had the exact same question. Thanks for answering Milo.