Computer Science Large Practical:

Quick quiz on Objective-C

Stephen Gilmore

School of Informatics

Friday 19th October, 2012

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Question: Does this program print Yes, No or neither?

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Answer: it prints Yes.

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. . . it prints Yes.

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Question: Does this program print Yes, No or neither?

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Answer: it prints No.

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. . . it prints No.

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Question: Does this program print Yes, No or neither?

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Answer: neither, it throws an exception.

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. . . neither, it throws an exception.

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Question: Does this program print Yes, No or neither?

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Answer: it prints No.

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. . . it prints No.

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Question: Does this program print Yes, No or neither?

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Answer: it prints No, because we are using pointer equality

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. . . it prints No, because we are using pointer equality

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Question: Does this program print Yes, No or neither?

shot 2012-10-19 at 10.24.29.png

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Answer: it prints Yes, because we are using contentequality

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. . . it prints Yes, because we are using content equality

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Question: Does this program print Yes, No or neither?

shot 2012-10-19 at 10.41.28.png

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Answer: neither, it throws an exception because we forgotto call init

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. . . neither, it throws an exception because we forgot to call init

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