16 lines
261 B
Racket
16 lines
261 B
Racket
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#lang racket
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(define fish%
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(class object%
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(super-new)
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;; an instance variable & constructor argument
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(init-field size)
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;; a new method
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(define/public (eat)
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(displayln "gulp!"))))
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;; constructing an instance
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(new fish% [size 50])
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