ELet.java

/***************************************************************************
   Copyright 2012 Emily Estes

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
***************************************************************************/
package net.metanotion.simpletemplate.interpreter;


import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import net.metanotion.util.ChainedDictionary;
import net.metanotion.util.Dictionary;
import net.metanotion.util.MapDictionaryAdapter;
import net.metanotion.scripting.ObjectServer;

final class ELet implements Element {
	private static final Logger logger = LoggerFactory.getLogger(ELet.class);

	private final EJSObj vars;
	private final Element[] body;
	public ELet(EJSObj vars, Element[] body) {
		this.vars = vars;
		this.body = body;
	}

	@Override public Object eval(final ObjectServer os, final Object env) {
		logger.debug("LET ENV *** " + env.getClass());
		Dictionary<String,Object> localEnvironment = new MapDictionaryAdapter<String,Object>(vars.eval(os, env));
		if(env instanceof Dictionary) {
			localEnvironment = new ChainedDictionary(localEnvironment, (Dictionary<String,Object>) env);
		}
		final LocalObjectServer localObjectServer = new LocalObjectServer(localEnvironment, os);
		Object result = null;
		for(Element e: body) { result = e.eval(localObjectServer, localObjectServer); }
		logger.debug("LET result: " + result.getClass());
		return result;
	}
}