48 lines
1.2 KiB
Java
48 lines
1.2 KiB
Java
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/*
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* Name: Mike Cifelli
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* Course: CIS 443 - Programming Languages
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* Assignment: Lisp Interpreter 1
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*/
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package eval;
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import parser.*;
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/**
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* <code>QUOTE</code> represents the QUOTE form in Lisp.
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*/
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public class QUOTE extends LispFunction {
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// The number of arguments that QUOTE takes.
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private static final int NUM_ARGS = 1;
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public SExpression call(Cons argList) {
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// retrieve the number of arguments passed to QUOTE
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int argListLength = LENGTH.getLength(argList);
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// make sure we have received exactly one argument
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if (argListLength != NUM_ARGS) {
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Cons originalSExpr = new Cons(new Symbol("QUOTE"), argList);
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String errMsg = "too " +
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((argListLength > NUM_ARGS) ? "many" : "few") +
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" arguments given to QUOTE: " + originalSExpr;
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throw new RuntimeException(errMsg);
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}
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return argList.getCar();
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}
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/**
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* Determine if the arguments passed to this Lisp function should be
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* evaluated.
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*
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* @return
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* <code>false</code>
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*/
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public boolean evaluateArguments() {
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return false;
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}
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}
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