Module: Memoit

Defined in:
lib/memoit.rb,
lib/memoit/version.rb

Constant Summary collapse

VERSION = 
"0.1.2"

Instance Method Summary collapse

Instance Method Details

#memoize(name) ⇒ Object

Memoize the method with the given name.

Examples:

class Foo
  memoize def bar(value)
    expensive_calculation(value)
  end
end



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# File 'lib/memoit.rb', line 13

def memoize(name)
  ivar_name = "@_memo_#{name}".to_sym
  mod = Module.new do
    define_method(name) do |*args, &block|
      return super(*args, &block) if block
      cache = instance_variable_get(ivar_name) || instance_variable_set(ivar_name, {})
      hash = args.hash
      if cache.has_key?(hash)
        cache[hash]
      else
        cache[hash] = super(*args)
      end
    end
  end
  prepend mod
end