AddEventualEmptyTransformationToProductions.java

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * This file is part of SableCC.                             *
 * See the file "LICENSE" for copyright information and the  *
 * terms and conditions for copying, distribution and        *
 * modification of SableCC.                                  *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

package org.sablecc.sablecc;

import org.sablecc.sablecc.analysis.*;
import org.sablecc.sablecc.node.*;

import java.util.LinkedList;

/*
 * AddEventualEmptyTransformationToProductions
 * 
 * This class provide the second part of the support by SableCC3.x.x 
 * for SableCC2.x.x grammars.
 * Its role is to add Productions and Alternatives transformations within
 * Productions section.
 * Assuming this is run after the eventual AddAstProductions it also add
 * default transformations to productions and alternatives which have not
 * not specified them.
 */

@SuppressWarnings("rawtypes")
public class AddEventualEmptyTransformationToProductions extends DepthFirstAdapter {
    private String currentProd;
//  private String currentAlt;

    private ResolveIds ids;
    private ResolveAstIds ast_ids;

    public AddEventualEmptyTransformationToProductions(ResolveIds ids, ResolveAstIds ast_ids) {
        this.ids = ids;
        this.ast_ids = ast_ids;
    }

    @Override
    public void inAProd(AProd node) {
        currentProd = (String) ids.names.get(node);

    /* IfStmt there is no transformation specified for the production
     * and there is no AST production which has the same name as the current
     * CST production, this production is transformed into an empty
     */
        if (node.getArrow() == null && ast_ids.ast_prods.get(currentProd) == null) {
            node.setArrow(new TArrow(node.getId().getLine(), node.getId().getPos() + node.getId().getText().length()));
            node.setProdTransform(new LinkedList());

            AAlt[] alts = (AAlt[]) node.getAlts().toArray(new AAlt[0]);

            for (int i = 0; i < alts.length; i++) {
                alts[i].apply(new DepthFirstAdapter() {
                    @Override
                    public void inAAlt(AAlt node) {
                        if (node.getAltTransform() != null && ((AAltTransform) node.getAltTransform()).getTerms().size() > 0) {
                            error(((AAltTransform) node.getAltTransform()).getLBrace());
                        }
                        node.setAltTransform(new AAltTransform(new TLBrace(), new LinkedList(), new TRBrace()));
                    }
                }
                );
            }
        }
    }

    private static void error(Token token) {
        throw new RuntimeException(
                "[" + token.getLine() + "," + token.getPos() + "] " +
                        "This alternative transformation should be transformed to {-> } ");
    }

}