/interpreter/tags/at2dist030708/src/edu/vub/at/objects/natives/grammar/AGMessageCreation.java
Java | 138 lines | 60 code | 16 blank | 62 comment | 3 complexity | 3a278ffa524d64fe5e3e4650c77d73e7 MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * AGMessageCreation.java created on 10-aug-2006 at 14:10:17 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.natives.grammar; 29 30import edu.vub.at.eval.Evaluator; 31import edu.vub.at.exceptions.InterpreterException; 32import edu.vub.at.exceptions.XTypeMismatch; 33import edu.vub.at.objects.ATContext; 34import edu.vub.at.objects.ATMessage; 35import edu.vub.at.objects.ATObject; 36import edu.vub.at.objects.ATTable; 37import edu.vub.at.objects.grammar.ATExpression; 38import edu.vub.at.objects.grammar.ATMessageCreation; 39import edu.vub.at.objects.grammar.ATSymbol; 40import edu.vub.at.objects.natives.NATTable; 41import edu.vub.at.objects.natives.NATText; 42 43/** 44 * The common superclass of AGAsyncMessageCreation and AGMethodInvocationCreation. 45 * This class serves as a common repository for both kinds of first-class message AG elements. 46 * 47 * @author tvcutsem 48 */ 49public abstract class AGMessageCreation extends AGExpression implements ATMessageCreation { 50 51 private final ATSymbol selector_; 52 private final ATTable arguments_; 53 private final ATExpression annotations_; 54 55 public AGMessageCreation(ATSymbol sel, ATTable args, ATExpression annotations) { 56 selector_ = sel; 57 arguments_ = args; 58 annotations_ = annotations; 59 } 60 61 public ATSymbol base_selector() { return selector_; } 62 63 public ATTable base_arguments() { return arguments_; } 64 65 public ATExpression base_annotations() { return annotations_; } 66 67 public boolean isMessageCreation() { 68 return true; 69 } 70 71 public ATMessageCreation asMessageCreation() throws XTypeMismatch { 72 return this; 73 } 74 75 /** 76 * To evaluate a message send, transform the selector 77 * and evaluated arguments into a first-class Message object. 78 * It is important to note that the arguments are all eagerly evaluated. 79 * 80 * The annotation to the message send is either included in the generated message 81 * as a table of type tags, if it evaluates to a table, or as a one-sized table of the 82 * evaluated annotation. This means that <code>o.m(x)@y</code> is 83 * evaluated as <code>o.m(x)@[y]</code>, for example. 84 * 85 * AGMSG(sel,arg,ann).eval(ctx) = NATMSG(sel, map eval(ctx) over arg, (a:ann.eval(ctx).isTable? ? a : [a])) 86 * 87 * @return a first-class method invocation 88 */ 89 public ATObject meta_eval(ATContext ctx) throws InterpreterException { 90 NATTable evaluatedArgs = Evaluator.evaluateArguments(arguments_.asNativeTable(), ctx); 91 ATObject annotations = annotations_.meta_eval(ctx); 92 return this.createMessage(ctx, 93 selector_, 94 evaluatedArgs, 95 (annotations.isTable()) ? annotations.asTable() : NATTable.of(annotations)); 96 } 97 98 /** 99 * Quoting a message creation element returns a new quoted message creation element. 100 */ 101 public ATObject meta_quote(ATContext ctx) throws InterpreterException { 102 return this.newQuoted(selector_.meta_quote(ctx).asSymbol(), 103 arguments_.meta_quote(ctx).asTable(), 104 annotations_.meta_quote(ctx).asExpression()); 105 } 106 107 public NATText meta_print() throws InterpreterException { 108 if (annotations_ == NATTable.EMPTY) { 109 return NATText.atValue(this.getMessageToken() + 110 selector_.meta_print().javaValue + 111 Evaluator.printAsList(arguments_).javaValue); 112 } else { 113 return NATText.atValue(this.getMessageToken() + 114 selector_.meta_print().javaValue + 115 Evaluator.printAsList(arguments_).javaValue + 116 "@" + annotations_.meta_print().javaValue); 117 } 118 } 119 120 /** 121 * Subclasses must implement this method in order to return a new instance of themselves 122 * parameterized with their quoted arguments. 123 */ 124 protected abstract ATObject newQuoted(ATSymbol quotedSel, ATTable quotedArgs, ATExpression quotedAnnotations); 125 126 /** 127 * Subclasses must implement this method such that the correct messaging token 128 * can be displayed when printing an AGMessageCreation element. 129 */ 130 protected abstract String getMessageToken(); 131 132 /** 133 * Subclasses must implement this method such that the correct kind of message is created 134 * for a given selector, evaluated arguments and annotation 135 */ 136 protected abstract ATMessage createMessage(ATContext ctx, ATSymbol selector, ATTable evaluatedArgs, ATTable annotations) throws InterpreterException; 137 138}