/*     ____ ____  ____ ____  ______                                     *\
**    / __// __ \/ __// __ \/ ____/    SOcos COmpiles Scala             **
**  __\_ \/ /_/ / /__/ /_/ /\_ \       (c) 2002, LAMP/EPFL              **
** /_____/\____/\___/\____/____/                                        **
\*                                                                      */

// $Id$

package scalac.ast;

import scalac.Global;
import scalac.Unit;
{#Imports#}

/**
 * A default transformer class. This class traverses the abstract
 * syntax tree but does not do any transformations.
 */
public class Transformer {

    //########################################################################
    // Public Fields

    /** The global environment */
    public final Global global;

    /** The tree factory */
    public final TreeFactory make;

    /** The tree copier */
    public final TreeCopier copy;

    /** A tree generator */
    public final TreeGen gen;

    //########################################################################
    // Public Constructors

    public Transformer(Global global) {
        this(global, global.make);
    }

    public Transformer(Global global, TreeFactory make) {
        this(global, make, new LazyTreeCopier(make));
    }

    public Transformer(Global global, TreeFactory make, TreeCopier  copy) {
        this.global = global;
        this.make = make;
        this.copy = copy;
        this.gen = global.treeGen;
    }

    //########################################################################
    // Public Methods

    public void apply(Unit[] units) {
        for (int i = 0; i < units.length; i++) apply(units[i]);
    }

    public void apply(Unit unit) {
        unit.global.log("transforming " + unit);
        unit.body = transform(unit.body);
    }

    public Tree transform(Tree tree) {
        {#TreeSwitch#}
    }

    public Template transform(Template tree) {
        return (Template)transform((Tree)tree);
    }

    {#TransformArrays#}

    //########################################################################
}