CHINDOGU: LEVENSHTEIN Y METHOD MISSNG

Transcript

1. CHINDOGU LEVENSHTEIN METHOD MISSING guadalajara.rb Tuesday, October 2, 12
2. ¿Que es un Chindogu? Es un invento que, aparentemente, es la solución ideal a un problema particular pero que en la práctica resulta todo lo contrario. Los inconvenientes adicionales suelen hacer que dicho ingenio sea inapropiado o absurdo. Tuesday, October 2, 12
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4. EN RUBY LAND • https://github.com/garybernhardt/base • https://github.com/tenderlove/enterprise Tuesday, October 2, 12
5. Distancia de Levenshtein el número mínimo de operaciones requeridas para transformar una cadena de caracteres en otra. Tuesday, October 2, 12
6. gem install levenshtein Tuesday, October 2, 12
7. Levenshtein.distance("attempt","attempt") => 0 Tuesday, October 2, 12
8. Levenshtein.distance("attempt","atempt") => 1 Tuesday, October 2, 12
9. Levenshtein.distance("attempt","atemp") => 2 Tuesday, October 2, 12
10. Levenshtein.distance("attempt","attemp") => 1 Tuesday, October 2, 12
11. ICANHAZTYPOS Tuesday, October 2, 12
12. LET’S WRITE TESTS Tuesday, October 2, 12
13. describe WTF do let(:wtf) { WTF.new } it "does just as expected" do wtf.attempt.should == "wtf" end end Tuesday, October 2, 12
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15. class WTF def attempt "wtf" end end Tuesday, October 2, 12
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17. describe WTF do let(:wtf) { WTF.new } it "does just as expected" do wtf.attempt.should == "wtf" end it "calls a method with distance 1" do wtf.attemp.should == "wtf" end it "calls another method with distance 1" do wtf.atempt.should == "wtf" end end Tuesday, October 2, 12
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19. NoMethodError: undefined method Tuesday, October 2, 12
20. method_missing Permite interceptar mensajes que no se puede “responder” y hacer con ellos lo que queramos. Te permite interceptar NoMethodError y hacer lo que quieras desde alli. Tuesday, October 2, 12
21. def method_missing(name, *args, &block) # -------------- end Tuesday, October 2, 12
22. module ICANHAZTYPOS def method_missing(name, *args, &block) # -------------- end end Tuesday, October 2, 12
23. class WTF include ICANHAZTYPOS def attempt "wtf" end end Tuesday, October 2, 12
24. require 'levenshtein' module ICANHAZTYPOS def method_missing(name, *args, &block) # -------------- end end Tuesday, October 2, 12
25. require 'levenshtein' module ICANHAZTYPOS def method_missing(name, *args, &block) methods.each do |m| end end end Tuesday, October 2, 12
26. require 'levenshtein' module ICANHAZTYPOS def method_missing(name, *args, &block) methods.each do |m| return self.send(m) if Levenshtein.distance(m.to_s, name.to_s) == 1 end end end Tuesday, October 2, 12
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28. class WTF include ICANHAZTYPOS def attempt "wtf" end end Tuesday, October 2, 12
29. class WTF include ICANHAZTYPOS def attempt "wtf" end end ruby-1.9.3-p0 :001 > w = WTF.new => #<WTF:0x007ff7e0c74428> ruby-1.9.3-p0 :002 > w.attempt => "wtf" Tuesday, October 2, 12
30. class WTF include ICANHAZTYPOS def attempt "wtf" end end ruby-1.9.3-p0 :001 > w = WTF.new => #<WTF:0x007ff7e0c74428> ruby-1.9.3-p0 :002 > w.attempt => "wtf" ruby-1.9.3-p0 :003 > w.atempt => "wtf" ruby-1.9.3-p0 :004 > w.attemp => "wtf" Tuesday, October 2, 12
31. ruby-1.9.3-p0 :002 > w.winning? => [:attempt, :method_missing, :nil?, :===, :=~, :! ~, :eql?, :hash, :<=>, :class, :singleton_class, :clone, :dup, :initialize_dup, :initialize_clone, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :frozen?, :to_s, :inspect, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :respond_to_missing?, :extend, :display, :method, :public_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :==, :equal?, :!, :! =, :instance_eval, :instance_exec, :__send__, :__id__] Tuesday, October 2, 12
32. ruby-1.9.3-p0 :002 > w.winning? => [:attempt, :method_missing, :nil?, :===, :=~, :! ~, :eql?, :hash, :<=>, :class, :singleton_class, :clone, :dup, :initialize_dup, :initialize_clone, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :frozen?, :to_s, :inspect, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :respond_to_missing?, :extend, :display, :method, :public_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :==, :equal?, :!, :! =, :instance_eval, :instance_exec, :__send__, :__id__] Queremos que EXPLOTE Leveshtein > 1 Tuesday, October 2, 12
33. module ICANHAZTYPOS def method_missing(name, *args, &block) methods.each do |m| return self.send(m) if Levenshtein.distance(m.to_s, name.to_s) == 1 end end end Retorna los methods ya que nada paso en el loop Tuesday, October 2, 12
34. EL BUG Tuesday, October 2, 12
35. it "booms for Levenshtein > 1" do expect { wtf.winning? }.to raise_error(NoMethodError) end Tuesday, October 2, 12
36. module ICANHAZTYPOS def method_missing(name, *args, &block) methods.each do |m| return self.send(m) if Levenshtein.distance(m.to_s, name.to_s) == 1 end super end end Tuesday, October 2, 12
37. ruby-1.9.3-p0 :002 > w.winning? NoMethodError: undefined method `winning?' for #<WTF:0x007f8392af3468> from /Users/ivan/Desktop/ ICANHAZTYPOS_spec.rb:9:in ` method_missing' Tuesday, October 2, 12
38. @ivanacostarubio + info Tuesday, October 2, 12