cardinality.rb in rails-erd-1.0.0

- old
+ new

@@ -2,33 +2,33 @@
   class Domain
     class Relationship
       class Cardinality
         extend Inspectable
         inspection_attributes :source_range, :destination_range
-        
+
         N = Infinity = 1.0/0 # And beyond.
-      
+
         CLASSES = {
           [1, 1] => :one_to_one,
           [1, N] => :one_to_many,
           [N, 1] => :many_to_one,
           [N, N] => :many_to_many
         } # @private :nodoc:
 
         # Returns a range that indicates the source (left) cardinality.
         attr_reader :source_range
-      
+
         # Returns a range that indicates the destination (right) cardinality.
         attr_reader :destination_range
 
         # Create a new cardinality based on a source range and a destination
         # range. These ranges describe which number of values are valid.
         def initialize(source_range, destination_range) # @private :nodoc:
           @source_range = compose_range(source_range)
           @destination_range = compose_range(destination_range)
         end
-      
+
         # Returns the name of this cardinality, based on its two cardinal
         # numbers (for source and destination). Can be any of
         # +:one_to_one:+, +:one_to_many+, or +:many_to_many+. The name
         # +:many_to_one+ also exists, but Rails ERD always normalises these
         # kinds of relationships by inversing them, so they become
@@ -42,68 +42,68 @@
         #   cardinality.one_to_many?
         #   #=> false
         def name
           CLASSES[cardinality_class]
         end
-      
+
         # Returns +true+ if the source (left side) is not mandatory.
         def source_optional?
           source_range.first < 1
         end
-      
+
         # Returns +true+ if the destination (right side) is not mandatory.
         def destination_optional?
           destination_range.first < 1
         end
-      
+
         # Returns the inverse cardinality. Destination becomes source, source
         # becomes destination.
         def inverse
           self.class.new destination_range, source_range
         end
-      
+
         CLASSES.each do |cardinality_class, name|
           class_eval <<-RUBY
             def #{name}?
               cardinality_class == #{cardinality_class.inspect}
             end
           RUBY
         end
-      
+
         def ==(other) # @private :nodoc:
           source_range == other.source_range and destination_range == other.destination_range
         end
-      
+
         def <=>(other) # @private :nodoc:
           (cardinality_class <=> other.cardinality_class).nonzero? or
           compare_with(other) { |x| x.source_range.first + x.destination_range.first }.nonzero? or
           compare_with(other) { |x| x.source_range.last + x.destination_range.last }.nonzero? or
           compare_with(other) { |x| x.source_range.last }.nonzero? or
           compare_with(other) { |x| x.destination_range.last }
         end
-      
+
         # Returns an array with the cardinality classes for the source and
         # destination of this cardinality. Possible return values are:
         # <tt>[1, 1]</tt>, <tt>[1, N]</tt>, <tt>[N, N]</tt>, and (in theory)
         # <tt>[N, 1]</tt>.
         def cardinality_class
           [source_cardinality_class, destination_cardinality_class]
         end
-      
+
         protected
 
         # The cardinality class of the source (left side). Either +1+ or +Infinity+.
         def source_cardinality_class
           source_range.last == 1 ? 1 : N
         end
-      
+
         # The cardinality class of the destination (right side). Either +1+ or +Infinity+.
         def destination_cardinality_class
           destination_range.last == 1 ? 1 : N
         end
-      
+
         private
-      
+
         def compose_range(r)
           return r..r if r.kind_of?(Integer) && r > 0
           return (r.begin)..(r.end - 1) if r.exclude_end?
           r
         end