/interpreter/tags/at_build150307/src/edu/vub/at/objects/natives/grammar/AGTabulation.java
Java | 94 lines | 39 code | 10 blank | 45 comment | 0 complexity | baca1128d872c845454bb173c2c34354 MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * AGTabulation.java created on 26-jul-2006 at 16:19:54 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.exceptions.XIllegalIndex; 32import edu.vub.at.exceptions.XTypeMismatch; 33import edu.vub.at.objects.ATContext; 34import edu.vub.at.objects.ATNumber; 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.ATTabulation; 39import edu.vub.at.objects.natives.NATText; 40 41/** 42 * @author tvc 43 * 44 * The native implementation of a tabulaton AG element. 45 */ 46public final class AGTabulation extends AGExpression implements ATTabulation { 47 48 private final ATExpression tblExp_; 49 private final ATExpression idxExp_; 50 51 public AGTabulation(ATExpression tbl, ATExpression idx) { 52 tblExp_ = tbl; 53 idxExp_ = idx; 54 } 55 56 public ATExpression base_getTableExpression() { return tblExp_; } 57 58 public ATExpression base_getIndexExpression() { return idxExp_; } 59 60 /** 61 * To evaluate a tabulation, evaluate the tabulation expression to a table, 62 * evaluate the index expression into a valid index, and then access the table at the given index slot. 63 * 64 * AGTBL(tbl,idx).eval(ctx) = tbl.eval(ctx).at(idx.eval(ctx)) 65 * 66 * @return the value of the indexed table slot. 67 */ 68 public ATObject meta_eval(ATContext ctx) throws InterpreterException { 69 ATTable tab = tblExp_.meta_eval(ctx).asTable(); 70 ATNumber idx = null; 71 try { 72 idx = idxExp_.meta_eval(ctx).asNumber(); 73 } catch (XTypeMismatch e) { 74 throw new XIllegalIndex(e.getMessage()); 75 } 76 return tab.base_at(idx); 77 } 78 79 /** 80 * Quoting a tabulation results in a new quoted tabulation 81 * 82 * AGTBL(tbl,idx).quote(ctx) = AGTBL(tbl.quote(ctx),idx.quote(ctx)) 83 */ 84 public ATObject meta_quote(ATContext ctx) throws InterpreterException { 85 return new AGTabulation(tblExp_.meta_quote(ctx).asExpression(), 86 idxExp_.meta_quote(ctx).asExpression()); 87 } 88 89 public NATText meta_print() throws InterpreterException { 90 return NATText.atValue(tblExp_.meta_print().javaValue + "[" + 91 idxExp_.meta_print().javaValue + "]"); 92 } 93 94}