Module: FetchIn

Included in:
Array, Hash
Defined in:
lib/fetch_in.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.fetch_in(h, *keys) ⇒ Object 



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# File 'lib/fetch_in.rb', line 3

def fetch_in(h, *keys)
  keys.reduce(h) do |result,key|
    return nil if !result
    result[key]
  end
end

.store_in(h, *keys_and_value, &proc) ⇒ Object

store_in stores a value in a nested associative structure new levels in the structure are created as required, by the supplied Proc. if no Proc is supplied, new levels are created with the same class as the previous level



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# File 'lib/fetch_in.rb', line 14

def store_in(h, *keys_and_value, &proc)
  proc ||= lambda{|rx_key_stack| rx_key_stack[-1][0].class.new}
  keys = keys_and_value[0..-2]
  value = keys_and_value[-1]

  # find or create the last associative receiver in the chain to the value
  last_rx = keys[0..-2].reduce([h,[]]) do |(rx,rx_key_stack),key|
    rx_key_stack = rx_key_stack << [rx,key]
    rx[key] = proc.call(rx_key_stack) if !rx[key]
    [rx[key], rx_key_stack]
  end[0]

  # set the value
  last_rx[keys[-1]]=value
end

Instance Method Details

#fetch_in(*keys) ⇒ Object 



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# File 'lib/fetch_in.rb', line 31

def fetch_in(*keys)
  FetchIn.fetch_in(self, *keys)
end

#store_in(*keys_and_value, &proc) ⇒ Object

store_in stores a value in a nested associative structure new levels in the structure are created as required, by the supplied Proc. if no Proc is supplied, new levels are created with the same class as the previous level



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# File 'lib/fetch_in.rb', line 39

def store_in(*keys_and_value, &proc)
  FetchIn.store_in(self, *keys_and_value, &proc)
end