/interpreter/tags/at_build150307/src/edu/vub/at/objects/ATMethod.java

 1/**
 2 * AmbientTalk/2 Project
 3 * ATMethod.java created on Jul 24, 2006 at 9:42:24 PM
 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;
31import edu.vub.at.objects.grammar.ATBegin;
32import edu.vub.at.objects.grammar.ATSymbol;
33
34/**
35 * ATMethods are ambienttalk's representation of methods as named functions. These
36 * functions do not close over an environment allowing for them to be shared between 
37 * different clones. The environment is to be supplied during lookup (which wraps 
38 * ATMethods into ATClosures). As a consequence it is not possible to
39 * get hold of an ATMethod at the base-level (since lookup implies wrapping)
40 * 
41 * TODO: turn base_getxxx into meta_getxxx?
42 * 
43 * @author smostinc
44 * @author tvcutsem
45 */
46public interface ATMethod extends ATObject {
47
48	/**
49	 * Applies the method to the given arguments in the given context.
50	 * The context is usually supplied by a closure and is necessary in order to
51	 * pair a method with its current receiver (its 'self')
52	 * 
53	 * The method itself is responsible for creating the appropriate 'call frame'
54	 * or activation record in which to define temporary variables and parameter bindings.
55	 * 
56	 * @param arguments the actual arguments, already eagerly evaluated
57	 * @param ctx the context in which to evaluate the method body, call frame not yet inserted
58	 * @return the value of evaluating the method body in a context derived from the given context
59	 */
60	public ATObject base_apply(ATTable arguments, ATContext ctx) throws InterpreterException;
61	
62	/**
63	 * Applies the method to the given arguments in the given context.
64	 * The context is usually supplied by a closure and is necessary in order to
65	 * pair a method with its current receiver (its 'self')
66	 * 
67	 * The method will use the given context 'as-is', and will *not* insert an additional call frame.
68	 * 
69	 * @param arguments the actual arguments, already eagerly evaluated
70	 * @param ctx the context in which to evaluate the method body, to be used without inserting a call frame
71	 * @return the value of evaluating the method body in the given context
72	 */
73	public ATObject base_applyInScope(ATTable arguments, ATContext ctx) throws InterpreterException;
74	
75	/**
76	 * Structural access to the name of the method. Note that all methods (defined
77	 * using def name( ...args... ) { ... } of def foo: arg bar: arg { ... }) retain
78	 * the name with which they were first bound. Literal blocks which may be created
79	 * outside of a definition are implicitly named 'lambda'.
80	 */
81	public ATSymbol base_getName() throws InterpreterException;
82	
83	/**
84	 * Structural access to the parameter list of the method,
85	 * which is normally a table of symbols.
86	 */
87	public ATTable base_getParameters() throws InterpreterException;
88	
89	/**
90	 * Structural access to the body of the method.
91	 */
92	public ATBegin base_getBodyExpression() throws InterpreterException;
93}