/interpreter/tags/at2-build270707/src/edu/vub/at/objects/ATContext.java

 1/**
 2 * AmbientTalk/2 Project
 3 * ATContext.java created on Jul 23, 2006 at 11:35:12 AM
 4 * (c) Programming Technology Lab, 2006 - 2007
 5 * Authors: Tom Van Cutsem & Stijn Mostinckx
 6 * 
 7 * Permission is hereby granted, free of charge, to any person
 8 * obtaining a copy of this software and associated documentation
 9 * files (the "Software"), to deal in the Software without
10 * restriction, including without limitation the rights to use,
11 * copy, modify, merge, publish, distribute, sublicense, and/or
12 * sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following
14 * conditions:
15 *
16 * The above copyright notice and this permission notice shall be
17 * included in all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
26 * OTHER DEALINGS IN THE SOFTWARE.
27 */
28package edu.vub.at.objects;
29
30import edu.vub.at.exceptions.InterpreterException;
31
32
33/**
34 * ATContext describes a triplet of scope pointers used during evaluation, namely
35 * one for the lexical scope (where the lookup starts for receiverless messages),
36 * one for the late-bound receiver and one for the parent object.
37 * 
38 * @author smostinc
39 */
40public interface ATContext extends ATObject {
41	
42	/**
43	 * Returns the lexical environment of the current context.
44	 * 
45	 * @return an {@link ATObject} representing the lexical environment of the current context.
46	 */
47	public ATObject base_lexicalScope() throws InterpreterException;
48	
49	/**
50	 * Returns the receiver (self pseudovariable) in the current context.
51	 * 
52	 * @return an {@link ATObject} representing the receiver in the current context.
53	 */
54	public ATObject base_self() throws InterpreterException;
55	
56	/*
57	 * Factory methods for creating new context objects as a delta w.r.t. the receiver context object.
58	 */
59	
60	/**
61	 * Returns a new context object for a given scope.
62	 * 
63	 * @param scope a scope.
64	 * @return a new context for the given scope.
65	 */
66	public ATContext base_withLexicalEnvironment(ATObject scope) throws InterpreterException;
67	
68	/**
69	 * Returns a new context object for the given dynamic receiver.
70	 * 
71	 * @param self representing the receiver (self pseudovariable).
72	 * @return a new context for the given dynamic receiver.
73	 */
74	public ATContext base_withDynamicReceiver(ATObject self) throws InterpreterException;
75
76}