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module RangeSpecs
class TenfoldSucc
include Comparable
attr_reader :n
def initialize(n)
@n = n
end
def <=>(other)
@n <=> other.n
end
def succ
self.class.new(@n * 10)
end
end
# Custom Range classes Xs and Ys
class Custom
include Comparable
attr_reader :length
def initialize(n)
@length = n
end
def eql?(other)
inspect.eql? other.inspect
end
alias :== :eql?
def inspect
'custom'
end
def <=>(other)
@length <=> other.length
end
end
class WithoutSucc
include Comparable
attr_reader :n
def initialize(n)
@n = n
end
def eql?(other)
inspect.eql? other.inspect
end
alias :== :eql?
def inspect
"WithoutSucc(#{@n})"
end
def <=>(other)
@n <=> other.n
end
end
class Xs < Custom # represent a string of 'x's
def succ
Xs.new(@length + 1)
end
def inspect
'x' * @length
end
end
class Ys < Custom # represent a string of 'y's
def succ
Ys.new(@length + 1)
end
def inspect
'y' * @length
end
end
class MyRange < Range
end
class ComparisonError < RuntimeError
end
end
|
