Module: Clevic::OrderedDataset

Included in:
CacheTable, TableSearcher
Defined in:
lib/clevic/ordered_dataset.rb

Overview

Provides a nice way of getting to Sequel::Dataset’s opts information

Including class must call dataset= before calling order_attributes

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#dataset ⇒ Object

Returns the value of attribute dataset.



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# File 'lib/clevic/ordered_dataset.rb', line 30

def dataset
  @dataset
end

Instance Method Details

#order_attributes ⇒ Object

returns a collection of [ attribute, (1|-1) ] where 1 is forward/asc (>) and -1 is backward/desc (<)



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# File 'lib/clevic/ordered_dataset.rb', line 11

def order_attributes
  if @order_attributes.nil?
    @order_attributes =
    dataset.opts[:order].map do |order_expr|
      case order_expr
      when Symbol
        [ order_expr, 1 ]

      when Sequel::SQL::OrderedExpression
        [ order_expr.expression, order_expr.descending ? -1 : 1 ]

      else
        raise "unknown order_expr: #{order_expr.inspect}"
      end
    end
  end
  @order_attributes
end