parser.cup

package com.pacheco.mee_3;

import java_cup.runtime.*;
import java.io.IOException;
import java.io.File;
import java.io.FileInputStream;
import java.lang.Object;
import java.util.*;
import java_cup.runtime.Symbol;

parser code {:
    protected Lexer lexer;
    private HashMap<String, Integer> symT;
    private String filename;

    public Parser(String filename) {
        this.filename = filename;
    }
:};

init with {:
    ComplexSymbolFactory f = new ComplexSymbolFactory();
    symbolFactory = f;
    File file = new File(filename);
    FileInputStream fis = null;
    try {
        fis = new FileInputStream(file);
    } catch (IOException e) {
        e.printStackTrace();
    } 
    lexer = new Lexer(f,fis);
    symT = new HashMap<String,Integer>();
:};

scan with {: return lexer.yylex(); :};

terminal Double NUMBER;
terminal        ADD;
terminal        MINUS;
terminal        MULT;
terminal        DIV;
terminal        POW;
terminal        O_BRACKET;
terminal        C_BRACKET;

non terminal S;
non terminal EXP;
non terminal NUM;

precedence left ADD, MINUS;
precedence left MULT, DIV;
precedence left POW;

S ::= EXP:e {: System.out.println("result: " + e); :}
    ;

EXP ::= EXP:e1 ADD EXP:e2             {: RESULT = (Double)e1 + (Double)e2; :}
      | EXP:e1 MINUS EXP:e2           {: RESULT = (Double)e1 - (Double)e2; :}
      | EXP:e1 MULT EXP:e2            {: RESULT = (Double)e1 * (Double)e2; :}
      | EXP:e1 DIV EXP:e2             {: RESULT = (Double)e1 / (Double)e2; :}
      | EXP:e1 POW EXP:e2             {: RESULT = Math.pow((Double)e1, (Double)e2); :}
      | O_BRACKET EXP:e C_BRACKET     {: RESULT = e; :}
      | NUM:n                         {: RESULT = n; :}
      ;

NUM ::= NUMBER:n        {: RESULT = n; System.out.println(n); :}
    ;