runtime.intrinsic._assoc.java Source code

Introduction

Here is the source code for runtime.intrinsic._assoc.java

Source

/**
 * ADOBE SYSTEMS INCORPORATED
 * Copyright 2009-2013 Adobe Systems Incorporated
 * All Rights Reserved.
 *
 * NOTICE: Adobe permits you to use, modify, and distribute
 * this file in accordance with the terms of the MIT license,
 * a copy of which can be found in the LICENSE.txt file or at
 * http://opensource.org/licenses/MIT.
 */
package runtime.intrinsic;

import com.google.common.collect.Iterators;
import runtime.rep.list.ListValue;
import runtime.rep.map.MapValue;
import runtime.rep.map.PersistentMap;
import runtime.rep.Tuple;

import java.util.Iterator;

/**
 * Create map from key and value lists.
 * For duplicate keys, last instance wins.
 * Equal list length is not required, value
 * list is cycled over if necessary.
 *
 * @author Basil Hosmer
 */
public final class _assoc extends IntrinsicLambda {
    public static final _assoc INSTANCE = new _assoc();
    public static final String NAME = "assoc";

    public String getName() {
        return NAME;
    }

    public Object apply(final Object arg) {
        final Tuple args = (Tuple) arg;
        return invoke((ListValue) args.get(0), (ListValue) args.get(1));
    }

    public static MapValue invoke(final ListValue keys, final ListValue vals) {
        if (vals.size() == 0)
            return PersistentMap.EMPTY;

        final PersistentMap result = PersistentMap.fresh();

        final Iterator<?> valiter = vals.size() >= keys.size() ? vals.iterator() : Iterators.cycle(vals);

        for (final Object key : keys)
            result.assocUnsafe(key, valiter.next());

        return result;
    }
}