org.armedbear.lisp.StackFrame Maven / Gradle / Ivy
/*
* StackFrame.java
*
* Copyright (C) 2009 Mark Evenson
* $Id$
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* As a special exception, the copyright holders of this library give you
* permission to link this library with independent modules to produce an
* executable, regardless of the license terms of these independent
* modules, and to copy and distribute the resulting executable under
* terms of your choice, provided that you also meet, for each linked
* independent module, the terms and conditions of the license of that
* module. An independent module is a module which is not derived from
* or based on this library. If you modify this library, you may extend
* this exception to your version of the library, but you are not
* obligated to do so. If you do not wish to do so, delete this
* exception statement from your version.
*/
package org.armedbear.lisp;
import static org.armedbear.lisp.Lisp.*;
public abstract class StackFrame
extends LispObject
{
@Override
public LispObject typep(LispObject typeSpecifier)
{
if (typeSpecifier == Symbol.STACK_FRAME)
return T;
if (typeSpecifier == BuiltInClass.STACK_FRAME)
return T;
return super.typep(typeSpecifier);
}
StackFrame next;
Environment env = null;
void setNext(StackFrame nextFrame) {
this.next = nextFrame;
}
StackFrame getNext() {
return this.next;
}
/** Sets the applicable environment for this stack frame to 'env',
* returning the last value.
*/
public Environment setEnv(Environment env) {
Environment e = this.env;
this.env = env;
return e;
}
/** Gets the current lexical environment of this stack frame. */
public Environment getEnv() {
return env;
}
public abstract LispObject toLispList();
public abstract SimpleString toLispString();
}