t_num.java

中山大学编译原理课程的一个实验

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package symbols;

import java.util.ArrayList;

/**
 *
 * @author Beeven
 */
public class T_NUM extends Terminal implements TerminalReduce{

    public Expr reduce(ArrayList<Expr> stack) {
        int post=stack.size()-1;
        Terminal t=(Terminal)stack.get(post);
        ArithExpr a=new ArithExpr((Num)t.token);
        stack.remove(post);
        stack.add(a);
        return a;
    }

}