example.md

이 글은 Canol Gokel님이 만든 Computer Programming using GNU Smalltalk를 읽고 정리한 것이다.

Example

"animal.st"
"A program which creates some animal classes to illustrate the object oriented concepts."

Object subclass: Animal [
  | name |

  animalNumber := 0.

  <comment: 'A class for defining animals.'>

  Animal class >> setAnimalNumber: number [
    "A class method to set the animal number."
    <category: 'accessing'>

    animalNumber := number.

    ^animalNumber
  ]

  Animal class >> getAnimalNumber [
    "A class method to get the animal number."
    <category: 'accessing'>

    ^animalNumber
  ]

  setName: newName [
    "An instance method to set the animal's name."
    <category: 'accessing'>

    name := newName.
  ]

  getName [
    "An instance method to get the animal's name."
    <category: 'accessing'>

    ^name
  ]
]

Animal subclass: Dog [
  <comment: 'A dog class.'>

  makeNoise [
    "An instance method to get the dog's noise."
    <category: 'accessing'>

    'Woof!' printNl.
  ]
]

Animal subclass: Cat [
  <comment: 'A cat class.'>

  makeNoise [
    "An instance method to get the cat's noise."
    <category: 'accessing'>

    'Miaow!' printNl.
  ]
]

dog := Dog new.
Animal setAnimalNumber: 1.
dog setName: 'Karabash'.
dog getName printNl.
dog makeNoise.

cat := Cat new.
Animal setAnimalNumber: 2.
cat setName: 'Minnosh'.
cat getName printNl.
cat makeNoise.

클래스 Object는 모든 클래스의 superclass이다. new 같이 미리 정의되어 있는 메소드를 가지고 있다.

Computer Programming with GNU Smalltalk