3 files changed, 28 insertions, 0 deletions
diff --git a/mrbgems/mruby-rational/mrbgem.rake b/mrbgems/mruby-rational/mrbgem.rake
index 496082709..93f5b601c 100644
--- a/mrbgems/mruby-rational/mrbgem.rake
+++ b/mrbgems/mruby-rational/mrbgem.rake
@@ -3,6 +3,7 @@ MRuby::Gem::Specification.new('mruby-rational') do |spec|
   spec.author  = 'mruby developers'
   spec.summary = 'Rational class'
 
+  spec.add_dependency 'mruby-metaprog', core: 'mruby-metaprog'
   spec.add_dependency 'mruby-object-ext', core: 'mruby-object-ext'
   spec.add_dependency 'mruby-numeric-ext', core: 'mruby-numeric-ext'
 end
diff --git a/mrbgems/mruby-rational/mrblib/rational.rb b/mrbgems/mruby-rational/mrblib/rational.rb
index ffadd55eb..7d5b87362 100644
--- a/mrbgems/mruby-rational/mrblib/rational.rb
+++ b/mrbgems/mruby-rational/mrblib/rational.rb
@@ -10,6 +10,18 @@ class Rational < Numeric
     "(#{to_s})"
   end
 
+  def to_f
+    @numerator.to_f / @denominator.to_f
+  end
+
+  def to_i
+    to_f.to_i
+  end
+
+  def to_r
+    self
+  end
+
   def to_s
     "#{numerator}/#{denominator}"
   end
diff --git a/mrbgems/mruby-rational/test/rational.rb b/mrbgems/mruby-rational/test/rational.rb
index a86f00690..85cebc316 100644
--- a/mrbgems/mruby-rational/test/rational.rb
+++ b/mrbgems/mruby-rational/test/rational.rb
@@ -9,6 +9,21 @@ assert 'Rational' do
   assert_equal [r.numerator, r.denominator], [5, 1]
 end
 
+assert 'Rational#to_f' do
+  assert_float Rational(2).to_f, 2.0
+  assert_float Rational(9, 4).to_f, 2.25
+  assert_float Rational(-3, 4).to_f, -0.75
+  assert_float Rational(20, 3).to_f, 6.666666666666667
+end
+
+assert 'Rational#to_i' do
+  assert_equal Rational(2, 3).to_i, 0
+  assert_equal Rational(3).to_i, 3
+  assert_equal Rational(300.6).to_i, 300
+  assert_equal Rational(98, 71).to_i, 1
+  assert_equal Rational(-30, 2).to_i, -15
+end
+
 assert 'Rational#*' do
   assert_rational Rational(2, 3)  * Rational(2, 3),  Rational(4, 9)
   assert_rational Rational(900)   * Rational(1),     Rational(900, 1)