17 lines
848 B
Plaintext
17 lines
848 B
Plaintext
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Suppose you have a class (like Food::Fish::Fishstick) that is derived,
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via its @ISA, from one or more superclasses (as Food::Fish::Fishstick is
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from Food::Fish, Life::Fungus, and Chemicals), and some of those
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superclasses may themselves each be derived, via its @ISA, from one or
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more superclasses (as above).
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When, then, you call a method in that class ($fishstick->calories), Perl
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first searches there for that method, but if it's not there, it goes
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searching in its superclasses, and so on, in a depth-first (or maybe
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"height-first" is the word) search. In the above example, it'd first
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look in Food::Fish, then Food, then Matter, then Life::Fungus, then
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Life, then Chemicals.
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This library, Class::ISA, provides functions that return that list --
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the list (in order) of names of classes Perl would search to find a
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method, with no duplicates.
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