24 lines
528 B
D
24 lines
528 B
D
class Delegator {
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string delegate() hasDelegate;
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string operation() {
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if (hasDelegate is null)
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return "Default implementation";
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return hasDelegate();
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}
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typeof(this) setDg(string delegate() dg) {
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hasDelegate = dg;
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return this;
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}
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}
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void main() {
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import std.stdio;
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auto dr = new Delegator;
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string delegate() thing = () => "Delegate implementation";
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writeln(dr.operation());
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writeln(dr.operation());
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writeln(dr.setDg(thing).operation());
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}
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