28 lines
429 B
Raku
28 lines
429 B
Raku
class Non-Delegate { }
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class Delegate {
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method thing {
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return "delegate implementation"
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}
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}
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class Delegator {
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has $.delegate is rw;
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method operation {
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$.delegate.^can( 'thing' ) ?? $.delegate.thing
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!! "default implementation"
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}
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}
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my Delegator $d .= new;
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say "empty: "~$d.operation;
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$d.delegate = Non-Delegate.new;
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say "Non-Delegate: "~$d.operation;
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$d.delegate = Delegate.new;
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say "Delegate: "~$d.operation;
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