/interpreter/tags/at2-build060407/src/edu/vub/at/objects/natives/grammar/AGSelection.java
Java | 84 lines | 29 code | 10 blank | 45 comment | 0 complexity | 0fd3e9db58934495702fcac630fcc380 MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * AGSelection.java created on 26-jul-2006 at 16:16:07 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.exceptions.InterpreterException; 31import edu.vub.at.objects.ATContext; 32import edu.vub.at.objects.ATObject; 33import edu.vub.at.objects.grammar.ATExpression; 34import edu.vub.at.objects.grammar.ATSelection; 35import edu.vub.at.objects.grammar.ATSymbol; 36import edu.vub.at.objects.natives.NATText; 37 38/** 39 * @author tvc 40 * 41 * The native implementation of a selection AG element. 42 */ 43public final class AGSelection extends AGExpression implements ATSelection { 44 45 private final ATExpression rcvExp_; 46 private final ATSymbol selector_; 47 48 public AGSelection(ATExpression rcv, ATSymbol sel) { 49 rcvExp_ = rcv; 50 selector_ = sel; 51 } 52 53 public ATExpression base_getReceiverExpression() { return rcvExp_; } 54 55 public ATSymbol base_getSelector() { return selector_; } 56 57 /** 58 * To evaluate a selection, evaluate the receiver expression to an object and select 59 * the slot with the given name from that object. 60 * 61 * AGSEL(rcv,sel).eval(ctx) = rcv.eval(ctx).meta_select(sel) 62 * 63 * @return the value of the selected slot. 64 */ 65 public ATObject meta_eval(ATContext ctx) throws InterpreterException { 66 ATObject receiver = rcvExp_.meta_eval(ctx); 67 return receiver.meta_select(receiver, selector_); 68 } 69 70 /** 71 * Quoting a selection results in a new quoted selection. 72 * 73 * AGSEL(rcv,sel).quote(ctx) = AGSEL(rcv.quote(ctx), sel.quote(ctx)) 74 */ 75 public ATObject meta_quote(ATContext ctx) throws InterpreterException { 76 return new AGSelection(rcvExp_.meta_eval(ctx).asExpression(), 77 selector_.meta_eval(ctx).asSymbol()); 78 } 79 80 public NATText meta_print() throws InterpreterException { 81 return NATText.atValue(rcvExp_.meta_print().javaValue + "." + selector_.meta_print().javaValue); 82 } 83 84}