/interpreter/tags/at2-build270707/src/edu/vub/at/objects/natives/grammar/AGApplication.java
Java | 112 lines | 55 code | 10 blank | 47 comment | 2 complexity | c9c9e726c9bb14c300ae4f607785330b MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * AGApplication.java created on 26-jul-2006 at 16:13:31 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.ATClosure; 34import edu.vub.at.objects.ATContext; 35import edu.vub.at.objects.ATObject; 36import edu.vub.at.objects.ATTable; 37import edu.vub.at.objects.grammar.ATApplication; 38import edu.vub.at.objects.grammar.ATExpression; 39import edu.vub.at.objects.natives.NATTable; 40import edu.vub.at.objects.natives.NATText; 41 42/** 43 * The native implementation of an application AG element. 44 * 45 * @author tvc 46 */ 47public final class AGApplication extends AGExpression implements ATApplication { 48 49 private final ATExpression funExp_; 50 private final ATTable arguments_; 51 52 public AGApplication(ATExpression fun, ATTable arg) { 53 funExp_ = fun; 54 arguments_ = arg; 55 } 56 57 public ATExpression base_function() { return funExp_; } 58 59 public ATTable base_arguments() { return arguments_; } 60 61 /** 62 * To evaluate a function application, evaluate the receiver expression to a function, then evaluate the arguments 63 * to the function application eagerly and apply the function. 64 * 65 * AGAPL(fun,arg).eval(ctx) = fun.eval(ctx).apply(map eval(ctx) over arg) 66 * 67 * @return the return value of the applied function. 68 */ 69 public ATObject meta_eval(ATContext ctx) throws InterpreterException { 70 // calls of the form f(x) are transformed into ctx.lex.call(`f, [x]) 71 if(funExp_.isSymbol()) { 72 NATTable args = Evaluator.evaluateArguments(arguments_.asNativeTable(), ctx); 73 ATObject result = null; 74 InvocationStack stack = InvocationStack.getInvocationStack(); 75 try { 76 stack.functionCalled(this, null, args); 77 result = ctx.base_lexicalScope().impl_callAccessor(funExp_.asSymbol(), args); 78 } finally { 79 stack.funcallReturned(result); 80 } 81 return result; 82 // calls of the form (expr)(x) are transformed into expr.eval(ctx).apply([x]) 83 } else { 84 ATClosure clo = funExp_.meta_eval(ctx).asClosure(); 85 NATTable args = Evaluator.evaluateArguments(arguments_.asNativeTable(), ctx); 86 ATObject result = null; 87 InvocationStack stack = InvocationStack.getInvocationStack(); 88 try { 89 stack.functionCalled(this, clo, args); 90 result = clo.base_apply(args); 91 } finally { 92 stack.funcallReturned(result); 93 } 94 return result; 95 } 96 } 97 98 /** 99 * Quoting an application results in a new quoted application. 100 * 101 * AGAPL(sel,arg).quote(ctx) = AGAPL(sel.quote(ctx), arg.quote(ctx)) 102 */ 103 public ATObject meta_quote(ATContext ctx) throws InterpreterException { 104 return new AGApplication(funExp_.meta_quote(ctx).asExpression(), 105 arguments_.meta_quote(ctx).asTable()); 106 } 107 108 public NATText meta_print() throws InterpreterException { 109 return NATText.atValue(funExp_.meta_print().javaValue + Evaluator.printAsList(arguments_).javaValue); 110 } 111 112}