8.6: Chapter Summary
- Page ID
- 36377
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- If you override = then you should override
hash
as well. - Override
postCopy
to correctly implement copying for your objects. - Send
self halt
to set a breakpoint. - Return
self subclassResponsibility
to make a method abstract. - To give an object a
String
representation you should overrideprintOn:
. - Override the hook method
initialize
to properly initialize instances. Number
methods automatically convert betweenFloats
,Fractions
andIntegers
.Fractions
truly represent rational numbers rather than floats.Characters
are unique instances.Strings
are mutable;Symbols
are not. Take care not to mutate string literals, however!Symbols
are unique;Strings
are not.Strings
andSymbols
areCollections
and therefore support the usualCollection
methods.