Posted almost 12 years ago. Visible to the public. Deprecated.

On memoizing methods that return a scope

The memoize method has long since been removed from ActiveSupport. Please use the memoizer gem which doesn't suffer from the issue below.

Be careful when memoizing Archive a method that returns a scope, e.g.:

def variants scoped(:conditions => { :name => name }) end memoize :variants

Because of the way memoize is implemented, that method now no longer returns a scope but its loaded target array.

The best solution is to use the Memoizer gem instead.

A workaround is to roll your own memoization:

def variants @variants ||= scoped(:conditions => { :name => name }) end
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Owner of this card:

Henning Koch
Last edit:
almost 5 years ago
by Henning Koch
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