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       1             : /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
       2             : /* This Source Code Form is subject to the terms of the Mozilla Public
       3             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       4             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       5             : 
       6             : 
       7             : /**
       8             :  * Represents a BooleanExpr, a binary expression that
       9             :  * performs a boolean operation between its lvalue and rvalue.
      10             : **/
      11             : 
      12             : #include "txExpr.h"
      13             : #include "txIXPathContext.h"
      14             : 
      15             : /**
      16             :  * Evaluates this Expr based on the given context node and processor state
      17             :  * @param context the context node for evaluation of this Expr
      18             :  * @param ps the ContextState containing the stack information needed
      19             :  * for evaluation
      20             :  * @return the result of the evaluation
      21             : **/
      22             : nsresult
      23           0 : BooleanExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)
      24             : {
      25           0 :     *aResult = nullptr;
      26             : 
      27             :     bool lval;
      28           0 :     nsresult rv = leftExpr->evaluateToBool(aContext, lval);
      29           0 :     NS_ENSURE_SUCCESS(rv, rv);
      30             : 
      31             :     // check for early decision
      32           0 :     if (op == OR && lval) {
      33           0 :         aContext->recycler()->getBoolResult(true, aResult);
      34             : 
      35           0 :         return NS_OK;
      36             :     }
      37           0 :     if (op == AND && !lval) {
      38           0 :         aContext->recycler()->getBoolResult(false, aResult);
      39             : 
      40           0 :         return NS_OK;
      41             :     }
      42             : 
      43             :     bool rval;
      44           0 :     rv = rightExpr->evaluateToBool(aContext, rval);
      45           0 :     NS_ENSURE_SUCCESS(rv, rv);
      46             : 
      47             :     // just use rval, since we already checked lval
      48           0 :     aContext->recycler()->getBoolResult(rval, aResult);
      49             : 
      50           0 :     return NS_OK;
      51             : } //-- evaluate
      52             : 
      53           0 : TX_IMPL_EXPR_STUBS_2(BooleanExpr, BOOLEAN_RESULT, leftExpr, rightExpr)
      54             : 
      55             : bool
      56           0 : BooleanExpr::isSensitiveTo(ContextSensitivity aContext)
      57             : {
      58           0 :     return leftExpr->isSensitiveTo(aContext) ||
      59           0 :            rightExpr->isSensitiveTo(aContext);
      60             : }
      61             : 
      62             : #ifdef TX_TO_STRING
      63             : void
      64           0 : BooleanExpr::toString(nsAString& str)
      65             : {
      66           0 :     if ( leftExpr ) leftExpr->toString(str);
      67           0 :     else str.AppendLiteral("null");
      68             : 
      69           0 :     switch ( op ) {
      70             :         case OR:
      71           0 :             str.AppendLiteral(" or ");
      72           0 :             break;
      73             :         default:
      74           0 :             str.AppendLiteral(" and ");
      75           0 :             break;
      76             :     }
      77           0 :     if ( rightExpr ) rightExpr->toString(str);
      78           0 :     else str.AppendLiteral("null");
      79             : 
      80           0 : }
      81             : #endif