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EQUALTO := T = K QUA TEXTHASHKEY.T; |
EQUALTO := T = K QUA TEXTHASHKEY.T; |
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END TEXTHASHKEY; |
END TEXTHASHKEY; |
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</lang> |
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=={{header|Smalltalk}}== |
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A class is declared abtract by responding to the query <tt>isAbstract</tt> with true, and defining the required protocol for subclasses to raise an error notification. Optionally, instance creation can be blocked. Typically, the IDE provides a menu function to generate these definitions automatically: |
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<lang smalltalk>someClass class >> isAbstract |
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^ true |
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someClass class >> new |
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^ self abstractClassInstantiationError |
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someClass >> method1 |
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^ self subclassResponsibility |
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</lang> |
</lang> |
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