16. Explain the difference between do:, collect:, reject:, select:, detect:, and (for bonus points) inject:into:. 17. Name some of Smalltalk's shortcomings. 18. What is the fundamental difference between an Array and an OrderedCollection? More Questions 19. What are true and false? 20. What is nil? 21. Without using any temporary variables, construct a method that sums the values of a collection of numbers. 22. Compare and contrast #deepCopy and #shallowCopy. 23. What is the result of evaluating the following method, and why? | oc copy | oc := OrderedCollection with: ' bc' copy with: ' bc' copy. copy := oc copy. 1 to: oc size do: [:index | (oc at: index) at: 1 put: $a ]. ^copy first 24. Which class implements the class method #new? 25. How do you customize the contents of what is displayed in an inspector? 26. What is the purpose of the instance method #hash? 27. What do the following terms mean? Abstract class, Overloading, Primitives, and State. 28. What is the reply of the following code fragment? ^OrderedCollection new add: #red add: #blue 29. What would be a better way to implement the following: | customerAction policyAction | customerAction := [ ... code fragment ... ]. policyAction := [ ... another code fragment ... ]. (self modelObject class = customer) ifTrue: [ customerAction value ] ifFalse: [ policyAction value ] 30. What is meant by the term 'lazy initialization'? 31. How can you display (write) information to the Transcript? 32. List and describe the different message formats supported by Smalltalk and state their order of precedence. 33. What is a VisualAge database access set? 34. What does abt stand for? 35. What is the difference between a Dictionary and an IdentityDictionary? 36. What is a message file (VisualAge)? 37. What does the term 'vote' refer to in the VisualAge drag&drop framework? 38. What roles do adaptors play in the VisualAge drag&drop framework? 39. What is the purpose of the PlatformFunction class (IBM Smalltalk)? 40. What is the purpose of the Signal class? 41. What is the purpose of the Delay class? 42. How do you change the system pointer (i.e. to an hourglass)(VisualAge)? 43. What is the answer of the following code? ^5 + 3; + 7 44. What does the term localization refer to? 45. Who can purge and salvage classes and applications (ENVY)? 46. Which messages can be sent to cause specific methods and classes to be included in a package(IBM Smalltalk)? 47. How do you remove the VisualAge splash screen? 48. What is the purpose of the method #finalInitialize (VisualAge)? 49. What is the POM Repository (IBM Smalltalk - Sparky persistence)? 50. What do the terms manage, map, and realize mean in the IBM Smalltalk view framework? 51. How can you change the system menu in VisualAge? 52. How can you read an environment variable (VisualAge) like 'Path'? 53. Why can't you unload a SortedCollectio using the ObjectDumper (IBM Smalltalk)? 54. What is the purpose of #become:?