def block_call (context, &block)
      args = []
      block.parameters.each do |parameter|
        args << context[parameter[1]]
      end
      block.call(*args)
    end
def block_call (context, &block)
      args = []
      block.parameters.each do |parameter|
        args << context[parameter[1]]
      end
      block.call(*args)
    end
Calls the block resolving the parameters by getting the parameter name from the
 given context.

 === Example

   context = :max => 10, :curr => 5, ratio => 0.15
   percentage = BlockHandler.call_block(context) { |max,curr| curr.to_f / max }