28 lines
763 B
Java
28 lines
763 B
Java
package function.builtin.cons;
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import function.ArgumentValidator;
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import function.FunctionNames;
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import function.LispFunction;
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import sexpression.Cons;
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import sexpression.SExpression;
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@FunctionNames({ "FIRST", "CAR" })
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public class FIRST extends LispFunction {
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private ArgumentValidator argumentValidator;
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public FIRST(String name) {
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this.argumentValidator = new ArgumentValidator(name);
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this.argumentValidator.setExactNumberOfArguments(1);
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this.argumentValidator.setEveryArgumentExpectedType(Cons.class);
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}
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@Override
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public SExpression call(Cons argumentList) {
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argumentValidator.validate(argumentList);
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Cons argument = (Cons) argumentList.getFirst();
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return argument.getFirst();
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}
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}
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