/*
***** BEGIN LICENSE BLOCK *****
* Version: CPL 1.0/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Common Public
* License Version 1.0 (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.eclipse.org/legal/cpl-v10.html
*
* 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.
*
* Copyright (C) 2001-2002 Jan Arne Petersen <jpetersen@uni-bonn.de>
* Copyright (C) 2001-2002 Benoit Cerrina <b.cerrina@wanadoo.fr>
* Copyright (C) 2002-2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
* Copyright (C) 2004 Thomas E Enebo <enebo@acm.org>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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* the provisions above, a recipient may use your version of this file under
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***** END LICENSE BLOCK *****/
package org.jruby.ast;
import java.util.List;
import org.jruby.Ruby;
import org.jruby.RubyLocalJumpError;
import org.jruby.ast.visitor.NodeVisitor;
import org.jruby.evaluator.ASTInterpreter;
import org.jruby.evaluator.Instruction;
import org.jruby.exceptions.JumpException;
import org.jruby.exceptions.RaiseException;
import org.jruby.javasupport.util.RuntimeHelpers;
import org.jruby.lexer.yacc.ISourcePosition;
import org.jruby.runtime.Block;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
/**
* Represents a while statement. This could be the both versions:
*
* while <condition>
* <body>
* end
*
* and
*
* <body> 'while' <condition>
*/
public class WhileNode extends Node {
private final Node conditionNode;
private final Node bodyNode;
private final boolean evaluateAtStart;
public boolean containsNonlocalFlow = false;
public WhileNode(ISourcePosition position, Node conditionNode, Node bodyNode) {
this(position, conditionNode, bodyNode, true);
}
public WhileNode(ISourcePosition position, Node conditionNode, Node bodyNode,
boolean evalAtStart) {
super(position, NodeType.WHILENODE);
assert conditionNode != null : "conditionNode is not null";
assert bodyNode != null : "bodyNode is not null";
this.conditionNode = conditionNode;
this.bodyNode = bodyNode;
this.evaluateAtStart = evalAtStart;
}
/**
* Accept for the visitor pattern.
* @param iVisitor the visitor
**/
public Instruction accept(NodeVisitor iVisitor) {
return iVisitor.visitWhileNode(this);
}
/**
* Gets the bodyNode.
* @return Returns a Node
*/
public Node getBodyNode() {
return bodyNode;
}
/**
* Gets the conditionNode.
* @return Returns a Node
*/
public Node getConditionNode() {
return conditionNode;
}
/**
* Determine whether this is while or do while
* @return true if you are a while, false if do while
*/
public boolean evaluateAtStart() {
return evaluateAtStart;
}
public List<Node> childNodes() {
return Node.createList(conditionNode, bodyNode);
}
@Override
public IRubyObject interpret(Ruby runtime, ThreadContext context, IRubyObject self, Block aBlock) {
IRubyObject result = null;
boolean firstTest = evaluateAtStart;
outerLoop: while (!firstTest || conditionNode.interpret(runtime,context,self, aBlock).isTrue()) {
firstTest = true;
loop: while (true) { // Used for the 'redo' command
try {
bodyNode.interpret(runtime,context, self, aBlock);
break loop;
} catch (RaiseException re) {
if (runtime.getLocalJumpError().isInstance(re.getException())) {
RubyLocalJumpError jumpError = (RubyLocalJumpError)re.getException();
IRubyObject reason = jumpError.reason();
// admittedly inefficient
if (reason.asJavaString().equals("break")) {
return jumpError.exit_value();
} else if (reason.asJavaString().equals("next")) {
break loop;
} else if (reason.asJavaString().equals("redo")) {
continue;
}
}
throw re;
} catch (JumpException.RedoJump rj) {
continue;
} catch (JumpException.NextJump nj) {
break loop;
} catch (JumpException.BreakJump bj) {
// JRUBY-530, while case
result = RuntimeHelpers.breakJumpInWhile(bj, context);
break outerLoop;
}
}
}
if (result == null) {
result = runtime.getNil();
}
return ASTInterpreter.pollAndReturn(context, result);
}
}