// @(#)TclGateway.java   5/2004
// Copyright (c) 1998-2004, Distributed Real-time Computing Lab (DRCL) 
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// 
// 1. Redistributions of source code must retain the above copyright notice,
//    this list of conditions and the following disclaimer. 
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution. 
// 3. Neither the name of "DRCL" nor the names of its contributors may be used
//    to endorse or promote products derived from this software without specific
//    prior written permission. 
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// 

package drcl.ruv;

import tcl.lang.InternalRep;
import tcl.lang.Interp;
import tcl.lang.ReflectObject;
import tcl.lang.TclObject;

public class TclGateway
{
	static ShellTcl tcl = null;
	static Interp interp = null;

	public static Object tcl(String script_) throws Exception
	{
		if (tcl == null) {
			tcl = new ShellTcl(".tcl_gateway");
			if (drcl.ruv.System.system == null)
				drcl.ruv.System.main(new String[]{"-u"});
			drcl.ruv.System.system.addTerminal(null, tcl, null, null);
			interp = tcl.getInterp();
		}
		TclObject raw_ = (TclObject)tcl.eval(script_);
		if (raw_ == null) return null;
		InternalRep rep_ = raw_.getInternalRep();
		if (rep_ instanceof ReflectObject)
			return ReflectObject.get(interp, raw_);
		else
			return raw_.toString();
	}
	
}
