Data commit

Task/Modular-arithmetic/Ruby/modular-arithmetic.rb

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+# stripped version of Andrea Fazzi's submission to Ruby Quiz #179
+
+class Modulo
+  include Comparable
+
+  def initialize(n = 0, m = 13)
+    @n, @m = n % m, m
+  end
+
+  def to_i
+    @n
+  end
+
+  def <=>(other_n)
+    @n <=> other_n.to_i
+  end
+
+  [:+, :-, :*, :**].each do |meth|
+    define_method(meth) { |other_n| Modulo.new(@n.send(meth, other_n.to_i), @m) }
+  end
+
+  def coerce(numeric)
+    [numeric, @n]
+  end
+
+end
+
+# Demo
+x, y = Modulo.new(10), Modulo.new(20)
+
+p x > y          # true
+p x == y         # false
+p [x,y].sort     #[#<Modulo:0x000000012ae0f8 @n=7, @m=13>, #<Modulo:0x000000012ae148 @n=10, @m=13>]
+p x + y          ##<Modulo:0x0000000117e110 @n=4, @m=13>
+p 2 + y          # 9
+p y + 2          ##<Modulo:0x00000000ad1d30 @n=9, @m=13>
+
+p x**100 + x +1  ##<Modulo:0x00000000ad1998 @n=1, @m=13>