/interpreter/tags/at2dist091109/src/edu/vub/at/objects/natives/grammar/AGMessageSend.java
Java | 119 lines | 56 code | 14 blank | 49 comment | 0 complexity | 53fa9642faf91c80d264ba68c1951d3b MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * AGMessageSend.java created on 26-jul-2006 at 16:03:06 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.eval.InvocationStack; 32import edu.vub.at.exceptions.InterpreterException; 33import edu.vub.at.objects.ATContext; 34import edu.vub.at.objects.ATMessage; 35import edu.vub.at.objects.ATNil; 36import edu.vub.at.objects.ATObject; 37import edu.vub.at.objects.ATTable; 38import edu.vub.at.objects.grammar.ATExpression; 39import edu.vub.at.objects.grammar.ATMessageSend; 40import edu.vub.at.objects.natives.NATText; 41 42import java.util.HashSet; 43import java.util.Set; 44 45/** 46 * @author tvc 47 * 48 * The native implementation of a synchronous message send AG element. 49 */ 50public final class AGMessageSend extends AGExpression implements ATMessageSend { 51 52 private final ATExpression rcvExp_; 53 private final ATExpression message_; 54 55 public AGMessageSend(ATExpression rcv, ATExpression msg) { 56 rcvExp_ = rcv; 57 message_ = msg; 58 } 59 60 public ATExpression base_receiverExpression() { return rcvExp_; } 61 62 public ATExpression base_messageExpression() { return message_; } 63 64 /** 65 * To evaluate a message send, evaluate the receiver expression into an object. 66 * Next, evaluate the message expression into a first-class message (asynchronous message or method invocation). 67 * The evaluation of the message send is delegated to the first-class message itself. 68 * 69 * AGMSGSEND(rcv,msg).eval(ctx) = msg.eval(ctx).meta_sendTo(rcv.eval(ctx), ctx.self) 70 * 71 * @return the value of the invoked method or NIL in the case of an asynchronous message send. 72 */ 73 public ATObject meta_eval(ATContext ctx) throws InterpreterException { 74 ATMessage msg = message_.meta_eval(ctx).asMessage(); 75 ATObject rcvr = rcvExp_.meta_eval(ctx); 76 ATObject result = null; 77 InvocationStack stack = InvocationStack.getInvocationStack(); 78 ATTable args = msg.base_arguments(); 79 try { 80 stack.methodInvoked(this, rcvr, args); 81 result = msg.base_sendTo(rcvr, ctx.base_receiver()); 82 } finally { 83 stack.methodReturned(result); 84 } 85 return result; 86 } 87 88 /** 89 * Quoting a message send returns a new quoted message send. 90 * 91 * AGMSGSEND(rcv,msg).quote(ctx) = AGMSGSEND(rcv.quote(ctx), msg.quote(ctx)) 92 */ 93 public ATObject meta_quote(ATContext ctx) throws InterpreterException { 94 return new AGMessageSend(rcvExp_.meta_quote(ctx).asExpression(), 95 message_.meta_quote(ctx).asExpression()); 96 } 97 98 public NATText meta_print() throws InterpreterException { 99 return NATText.atValue(rcvExp_.meta_print().javaValue + 100 ((message_.isMessageCreation()) ? "" : "<+") + message_.meta_print().javaValue); 101 } 102 103 /** 104 * FV(objExp <+ msgExp) = FV(objExp) U FV(msgExp) 105 */ 106 public Set impl_freeVariables() throws InterpreterException { 107 Set fvObjExp = rcvExp_.impl_freeVariables(); 108 fvObjExp.addAll(message_.impl_freeVariables()); 109 return fvObjExp; 110 } 111 112 113 public Set impl_quotedFreeVariables() throws InterpreterException { 114 Set qfv = rcvExp_.impl_quotedFreeVariables(); 115 qfv.addAll(message_.impl_quotedFreeVariables()); 116 return qfv; 117 } 118 119}