Ruby performance: rewrite class extension to compare array elements in C? -

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i have code extends ruby array class:

# extendes array class have methods giving same rspec functionality of # checking if array elements equals ones'. class array   def self.same_elements?(actual, expected)     extra_items   = difference_between_arrays(actual, expected)     missing_items = difference_between_arrays(expected, actual)     extra_items.empty? & missing_items.empty?   end    def has_same_elements?(expected)     extra_items   = self.class.difference_between_arrays(self, expected)     missing_items = self.class.difference_between_arrays(expected, self)     extra_items.empty? & missing_items.empty?   end    protected   def self.difference_between_arrays(array_1, array_2)     difference = array_1.dup     array_2.each |element|       if (index = difference.index(element))         difference.delete_at(index)       end     end     difference   end end

and spec:

describe array   before(:each)     @a = [1,2,3]     @b = [3,2,1]     @c = [1,2,3,4]     @d = [4,1,3]     @e = [1,2,3]   end   "should respond .same_elements?"     array.should respond_to(:same_elements?)   end   "should respond #has_same_elements?"     array.new.should respond_to(:has_same_elements?)   end    describe ".same_elements?"     "should return correct values"       array.same_elements?(@a,@a).should eq(true)       array.same_elements?(@a,@b).should eq(true)       array.same_elements?(@a,@c).should eq(false)       array.same_elements?(@a,@d).should eq(false)       array.same_elements?(@a,@e).should eq(true)        array.same_elements?(@b,@a).should eq(true)       array.same_elements?(@b,@b).should eq(true)       array.same_elements?(@b,@c).should eq(false)       array.same_elements?(@b,@d).should eq(false)       array.same_elements?(@b,@e).should eq(true)        array.same_elements?(@c,@a).should eq(false)       array.same_elements?(@c,@b).should eq(false)       array.same_elements?(@c,@c).should eq(true)       array.same_elements?(@c,@d).should eq(false)       array.same_elements?(@c,@e).should eq(false)        array.same_elements?(@d,@a).should eq(false)       array.same_elements?(@d,@b).should eq(false)       array.same_elements?(@d,@c).should eq(false)       array.same_elements?(@d,@d).should eq(true)       array.same_elements?(@d,@e).should eq(false)        array.same_elements?(@e,@a).should eq(true)       array.same_elements?(@e,@b).should eq(true)       array.same_elements?(@e,@c).should eq(false)       array.same_elements?(@e,@d).should eq(false)       array.same_elements?(@e,@e).should eq(true)     end   end    describe "#has_same_elements?"     "should return correct values"       @a.has_same_elements?(@a).should eq(true)       @a.has_same_elements?(@b).should eq(true)       @a.has_same_elements?(@c).should eq(false)       @a.has_same_elements?(@d).should eq(false)       @a.has_same_elements?(@e).should eq(true)        @b.has_same_elements?(@a).should eq(true)       @b.has_same_elements?(@b).should eq(true)       @b.has_same_elements?(@c).should eq(false)       @b.has_same_elements?(@d).should eq(false)       @b.has_same_elements?(@e).should eq(true)        @c.has_same_elements?(@a).should eq(false)       @c.has_same_elements?(@b).should eq(false)       @c.has_same_elements?(@c).should eq(true)       @c.has_same_elements?(@d).should eq(false)       @c.has_same_elements?(@e).should eq(false)        @d.has_same_elements?(@a).should eq(false)       @d.has_same_elements?(@b).should eq(false)       @d.has_same_elements?(@c).should eq(false)       @d.has_same_elements?(@d).should eq(true)       @d.has_same_elements?(@e).should eq(false)        @e.has_same_elements?(@a).should eq(true)       @e.has_same_elements?(@b).should eq(true)       @e.has_same_elements?(@c).should eq(false)       @e.has_same_elements?(@d).should eq(false)       @e.has_same_elements?(@e).should eq(true)     end   end end

this code apparently it's becoming slow large arrays.

is worth port methods in c performance reasons? how tackle issue? can suggest (recent) article build such functionality given i'm using ruby 2.0.0-p0?

update

benchmark between 2 proposed solutions:

                                           user     system      total        real (sort) instance method arr_1 vs arr_2      1.910000   0.030000   1.940000 (  1.935651) (set) instance method arr_1 vs arr_2       7.010000   0.360000   7.370000 (  7.377319) (sort) class method arr_1 vs arr_2         1.920000   0.030000   1.950000 (  1.952080) (set) class method arr_1 vs arr_2          6.610000   0.320000   6.930000 (  6.919273) (sort) instance method arr_1 vs arr_3      2.520000   0.090000   2.610000 (  2.620047) (set) instance method arr_1 vs arr_3       7.620000   0.330000   7.950000 (  7.951402) (sort) class method arr_1 vs arr_3         1.920000   0.030000   1.950000 (  1.943820) (set) class method arr_1 vs arr_3          8.130000   0.390000   8.520000 (  8.523959)

quick bm code:

require 'benchmark' require 'set'  class array   def self.same_elements_with_sort?(actual, expected)     actual.has_same_elements_with_sort?(expected)   end    def has_same_elements_with_sort?(expected)     self.sort == expected.sort   end    # -----    def self.same_elements?(actual, expected)     actual.to_set == expected.to_set   end    def has_same_elements?(expected)     array.same_elements?(self, expected)   end end  benchmark.bm(40) do|b|   arr_1 = (1..8000000).to_a.sample(40000)   arr_2 = (1..8000000).to_a.sample(40000)   arr_3 = arr_1    b.report('(sort) instance method arr_1 vs arr_2')     150.times { arr_1.has_same_elements_with_sort?(arr_2) }   end    b.report('(set) instance method arr_1 vs arr_2')     150.times { arr_1.has_same_elements?(arr_2) }   end    b.report('(sort) class method arr_1 vs arr_2')     150.times { array.same_elements_with_sort?(arr_1, arr_2) }   end    b.report('(set) class method arr_1 vs arr_2')     150.times { array.same_elements?(arr_1, arr_2) }   end    b.report('(sort) instance method arr_1 vs arr_3')     150.times { arr_1.has_same_elements_with_sort?(arr_3) }   end    b.report('(set) instance method arr_1 vs arr_3')     150.times { arr_1.has_same_elements?(arr_3) }   end    b.report('(sort) class method arr_1 vs arr_3')     150.times { array.same_elements_with_sort?(arr_1, arr_3) }   end    b.report('(set) class method arr_1 vs arr_3')     150.times { array.same_elements?(arr_1, arr_3) }   end end

your code comes rspec's matcharray. rspec computes extra_items , missing_items provide meaningful error message.

if don't need information, sort arrays:

class array   def self.same_elements?(actual, expected)     actual.has_same_elements?(expected)   end    def has_same_elements?(expected)     self.sort == expected.sort   end end

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