/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released
* May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Steve Yegge
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript.ast;
import org.mozilla.javascript.Token;
/**
* AST node representing an expression in a statement context. The node type is
* {@link Token#EXPR_VOID} if inside a function, or else
* {@link Token#EXPR_RESULT} if inside a script.
*/
public class ExpressionStatement extends AstNode {
private AstNode expr;
{
type = Token.EXPR_VOID;
}
/**
* Called by the parser to set node type to EXPR_RESULT
* if this node is not within a Function.
*/
public void setHasResult() {
type = Token.EXPR_RESULT;
}
public ExpressionStatement() {
}
/**
* Constructs a new {@code ExpressionStatement} wrapping
* the specified expression. Sets this node's position to the
* position of the wrapped node, and sets the wrapped node's
* position to zero. Sets this node's length to the length of
* the wrapped node.
* @param expr the wrapped expression
* @param hasResult {@code true} if this expression has side
* effects. If true, sets node type to EXPR_RESULT, else to EXPR_VOID.
*/
public ExpressionStatement(AstNode expr, boolean hasResult) {
this(expr);
if (hasResult) setHasResult();
}
/**
* Constructs a new {@code ExpressionStatement} wrapping
* the specified expression. Sets this node's position to the
* position of the wrapped node, and sets the wrapped node's
* position to zero. Sets this node's length to the length of
* the wrapped node.
* @param expr the wrapped expression
*/
public ExpressionStatement(AstNode expr) {
this(expr.getPosition(), expr.getLength(), expr);
}
public ExpressionStatement(int pos, int len) {
super(pos, len);
}
/**
* Constructs a new {@code ExpressionStatement}
* @param expr the wrapped {@link AstNode}.
* The {@code ExpressionStatement}'s bounds are set to those of expr,
* and expr's parent is set to this node.
* @throws IllegalArgumentException if {@code expr} is null
*/
public ExpressionStatement(int pos, int len, AstNode expr) {
super(pos, len);
setExpression(expr);
}
/**
* Returns the wrapped expression
*/
public AstNode getExpression() {
return expr;
}
/**
* Sets the wrapped expression, and sets its parent to this node.
* @throws IllegalArgumentException} if expression is {@code null}
*/
public void setExpression(AstNode expression) {
assertNotNull(expression);
expr = expression;
expression.setParent(this);
setLineno(expression.getLineno());
}
/**
* Returns true if this node has side effects
* @throws IllegalStateException if expression has not yet
* been set.
*/
@Override
public boolean hasSideEffects() {
return type == Token.EXPR_RESULT || expr.hasSideEffects();
}
@Override
public String toSource(int depth) {
StringBuilder sb = new StringBuilder();
sb.append(expr.toSource(depth));
sb.append(";\n");
return sb.toString();
}
/**
* Visits this node, then the wrapped statement.
*/
@Override
public void visit(NodeVisitor v) {
if (v.visit(this)) {
expr.visit(v);
}
}
}