/*
* Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
*
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.quercus.expr;
import com.caucho.quercus.Location;
import com.caucho.quercus.env.ArrayValue;
import com.caucho.quercus.env.ArrayValueImpl;
import com.caucho.quercus.env.Env;
import com.caucho.quercus.env.Value;
/**
* Represents a PHP array[] reference expression.
*/
public class ArrayTailExpr extends AbstractVarExpr {
protected final Expr _expr;
public ArrayTailExpr(Location location, Expr expr)
{
super(location);
_expr = expr;
}
public ArrayTailExpr(Expr expr)
{
_expr = expr;
}
/**
* Returns true for an expression that can be read (only $a[] uses this)
*/
public boolean canRead()
{
return false;
}
/**
* Returns the expr.
*/
public Expr getExpr()
{
return _expr;
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
public Value eval(Env env)
{
return env.error(getLocation(), "Cannot use [] as a read-value.");
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
@Override
public Value evalArg(Env env, boolean isTop)
{
return evalRef(env);
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
public Value evalRef(Env env)
{
Value obj = _expr.evalArray(env);
return obj.putRef();
}
/**
* Evaluates the expression, setting an array if unset..
*
* @param env the calling environment.
*
* @return the expression value.
*/
public Value evalArray(Env env)
{
Value obj = _expr.evalArray(env);
ArrayValue array = new ArrayValueImpl();
obj.put(array);
return array;
}
/**
* Evaluates the expression, assigning an object if unset..
*
* @param env the calling environment.
*
* @return the expression value.
*/
public Value evalObject(Env env)
{
Value array = _expr.evalArray(env);
Value value = env.createObject();
array.put(value);
return value;
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
public void evalAssign(Env env, Value value)
{
Value array = _expr.evalArray(env);
array.put(value);
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
public void evalUnset(Env env)
{
throw new UnsupportedOperationException();
}
public String toString()
{
return _expr + "[]";
}
}