| /* |
| * Copyright 2008 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| * use this file except in compliance with the License. You may obtain a copy of |
| * the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package com.google.gwt.dev.js.ast; |
| |
| import com.google.gwt.dev.jjs.SourceInfo; |
| |
| /** |
| * A JavaScript prefix or postfix operation. |
| */ |
| public abstract class JsUnaryOperation extends JsExpression { |
| |
| private JsExpression arg; |
| |
| private final JsUnaryOperator op; |
| |
| public JsUnaryOperation(SourceInfo sourceInfo, JsUnaryOperator op) { |
| this(sourceInfo, op, null); |
| } |
| |
| public JsUnaryOperation(SourceInfo sourceInfo, JsUnaryOperator op, |
| JsExpression arg) { |
| super(sourceInfo); |
| this.op = op; |
| this.arg = arg; |
| } |
| |
| public JsExpression getArg() { |
| return arg; |
| } |
| |
| public JsUnaryOperator getOperator() { |
| return op; |
| } |
| |
| @Override |
| public final boolean hasSideEffects() { |
| return op.isModifying() || arg.hasSideEffects(); |
| } |
| |
| public void setArg(JsExpression arg) { |
| this.arg = arg; |
| } |
| |
| public void traverse(JsVisitor v, JsContext<JsExpression> ctx) { |
| if (op.isModifying()) { |
| /* |
| * The delete operator is practically like an assignment of undefined, so |
| * for practical purposes we're treating it as an lvalue. |
| */ |
| arg = v.acceptLvalue(arg); |
| } else { |
| arg = v.accept(arg); |
| } |
| } |
| |
| } |