Basic implementation of Complex and Rational classes

1 files changed, 72 insertions, 28 deletions

diff --git a/mrbgems/mruby-rational/mrblib/rational.rb b/mrbgems/mruby-rational/mrblib/rational.rb
index 457c0488a..ffadd55eb 100644
--- a/mrbgems/mruby-rational/mrblib/rational.rb
+++ b/mrbgems/mruby-rational/mrblib/rational.rb
@@ -2,45 +2,89 @@ class Rational < Numeric
   def initialize(numerator = 0, denominator = 1)
     @numerator = numerator
     @denominator = denominator
+
+    _simplify
   end
 
-  attr_reader :numerator, :denominator
-end
+  def inspect
+    "(#{to_s})"
+  end
 
-def Rational(numerator = 0, denominator = 1)
-  Rational.new(numerator, denominator)
-end
+  def to_s
+    "#{numerator}/#{denominator}"
+  end
 
-module ForwardOperatorToRational
-  def __forward_operator_to_rational(op, &b)
-    original_operator_name = "__original_operator_#{op}_rational"
-    alias_method original_operator_name, op
-    define_method op do |rhs|
-      if rhs.is_a? Rational
-        Rational.new(self).send(op, rhs)
-      else
-        send(original_operator_name, rhs)
-      end
+  def *(rhs)
+    if rhs.is_a? Rational
+      Rational(numerator * rhs.numerator, denominator * rhs.denominator)
+    elsif rhs.is_a? Integer
+      Rational(numerator * rhs, denominator)
+    elsif rhs.is_a? Numeric
+      numerator * rhs / denominator
+    end
+  end
+
+  def +(rhs)
+    if rhs.is_a? Rational
+      Rational(numerator * rhs.denominator + rhs.numerator * denominator, denominator * rhs.denominator)
+    elsif rhs.is_a? Integer
+      Rational(numerator + rhs * denominator, denominator)
+    elsif rhs.is_a? Numeric
+      (numerator + rhs * denominator) / denominator
+    end
+  end
+
+  def -(rhs)
+    if rhs.is_a? Rational
+      Rational(numerator * rhs.denominator - rhs.numerator * denominator, denominator * rhs.denominator)
+    elsif rhs.is_a? Integer
+      Rational(numerator - rhs * denominator, denominator)
+    elsif rhs.is_a? Numeric
+      (numerator - rhs * denominator) / denominator
     end
   end
 
-  def __forward_operators_to_rational
-    __forward_operator_to_rational :+
-    __forward_operator_to_rational :-
-    __forward_operator_to_rational :*
-    __forward_operator_to_rational :/
+  def /(rhs)
+    if rhs.is_a? Rational
+      Rational(numerator * rhs.denominator, denominator * rhs.numerator)
+    elsif rhs.is_a? Integer
+      Rational(numerator, denominator * rhs)
+    elsif rhs.is_a? Numeric
+      numerator / rhs / denominator
+    end
+  end
 
-    singleton_class.undef_method :__forward_operator_to_rational
-    singleton_class.undef_method :__forward_operators_to_rational
+  def negative?
+    numerator.negative?
   end
+
+  def _simplify
+    a = numerator
+    b = denominator
+    a, b = b, a % b while !b.zero?
+    @numerator /= a
+    @denominator /= a
+  end
+
+  attr_reader :numerator, :denominator
 end
 
-class Fixnum
-  extend ForwardOperatorToRational
-  __forward_operators_to_rational
+def Rational(numerator = 0, denominator = 1)
+  Rational.new(numerator, denominator)
 end
 
-class Float
-  extend ForwardOperatorToRational
-  __forward_operators_to_rational
+[Fixnum, Float].each do |cls|
+  [:+, :-, :*, :/, :==].each do |op|
+    cls.instance_exec do
+      original_operator_name = "__original_operator_#{op}_rational"
+      alias_method original_operator_name, op
+      define_method op do |rhs|
+        if rhs.is_a? Rational
+          Rational(self).send(op, rhs)
+        else
+          send(original_operator_name, rhs)
+        end
+      end
+    end
+  end
 end
\ No newline at end of file