How false Is nil
Aug 04
2008
2008
Comments Off
Use nil when the return is a boolean value.
Use false when the return is either false or not true object.
Otherwise they have pretty much the same semantic:
nil == false => false nil.nil? => true false.nil? => false true.nil? => false if !nil && !false puts 'true' end if nil.nil? && !true.nil? puts 'true' end >> TrueClass.ancestors => [TrueClass, Object, Kernel] >> FalseClass.ancestors => [FalseClass, Object, Kernel] >> NilClass.ancestors => [NilClass, Object, Kernel]
