/interpreter/tags/at2dist091109/src/edu/vub/at/objects/grammar/ATDefType.java

 1/**
 2 * AmbientTalk/2 Project
 3 * ATDefType.java created on 18-feb-2007 at 14:06:09
 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.grammar;
29
30import edu.vub.at.objects.ATTable;
31
32/**
33 * The public interface to a type tag definition AG element.
34 * 
35 * Example: <code>deftype name</code>
36 * where <code>name</code> is a valid symbol.<br>
37 * A type tag can have multiple supertypes:
38 * <code>deftype c <: a, b</code> where <code>a</code>
39 * and <code>b</code> must evaluate to type tags
40 * 
41 * @author tvcutsem
42 */
43public interface ATDefType extends ATDefinition {
44	
45	/**
46	 * The name of the type to be defined must be a literal symbol
47	 * Example: <code>`{ deftype foo }.statements[1].typeName == `foo</code>
48	 * @return the name of the type
49	 */
50	public ATSymbol base_typeName();
51	
52	/**
53	 * A type can have zero, one or more parent types. 
54	 * Example: <code>`{ deftype foo <: bar, o.baz() }.statements[1].parentTypeExpressions == `[ bar, o.baz() ]</code>
55	 * @return a table with expressions that each must evaluate to a type
56	 */
57	public ATTable base_parentTypeExpressions();
58	
59}