text: /****************************************************************************
  **
  ** Copyright (C) 2015 The Qt Company Ltd.
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  **
  ** This file is part of the QtXmlPatterns module of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:LGPL21$
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  ** accordance with the commercial license agreement provided with the
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  ****************************************************************************/
  
  #include "qcommonsequencetypes_p.h"
  #include "qgenericsequencetype_p.h"
  #include "qoptimizationpasses_p.h"
  
  #include "qifthenclause_p.h"
  
  QT_BEGIN_NAMESPACE
  
  using namespace QPatternist;
  
  IfThenClause::IfThenClause(const Expression::Ptr &test,
                             const Expression::Ptr &then,
                             const Expression::Ptr &el) : TripleContainer(test, then, el)
  {
  }
  
  Item::Iterator::Ptr IfThenClause::evaluateSequence(const DynamicContext::Ptr &context) const
  {
      return m_operand1->evaluateEBV(context)
              ? m_operand2->evaluateSequence(context)
              : m_operand3->evaluateSequence(context);
  }
  
  Item IfThenClause::evaluateSingleton(const DynamicContext::Ptr &context) const
  {
      return m_operand1->evaluateEBV(context)
              ? m_operand2->evaluateSingleton(context)
              : m_operand3->evaluateSingleton(context);
  }
  
  bool IfThenClause::evaluateEBV(const DynamicContext::Ptr &context) const
  {
      return m_operand1->evaluateEBV(context)
              ? m_operand2->evaluateEBV(context)
              : m_operand3->evaluateEBV(context);
  }
  
  void IfThenClause::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const
  {
      if(m_operand1->evaluateEBV(context))
          m_operand2->evaluateToSequenceReceiver(context);
      else
          m_operand3->evaluateToSequenceReceiver(context);
  }
  
  Expression::Ptr IfThenClause::compress(const StaticContext::Ptr &context)
  {
      const Expression::Ptr me(TripleContainer::compress(context));
  
      if(me != this)
          return me;
  
      /* All operands mustn't be evaluated in order for const folding to
       * be possible. Let's see how far we get. */
  
      if(m_operand1->isEvaluated())
      {
          if(m_operand1->evaluateEBV(context->dynamicContext()))
              return m_operand2;
          else
              return m_operand3;
      }
      else
          return me;
  }
  
  QList<QExplicitlySharedDataPointer<OptimizationPass> > IfThenClause::optimizationPasses() const
  {
      return OptimizationPasses::ifThenPasses;
  }
  
  SequenceType::List IfThenClause::expectedOperandTypes() const
  {
      SequenceType::List result;
      result.append(CommonSequenceTypes::EBV);
      result.append(CommonSequenceTypes::ZeroOrMoreItems);
      result.append(CommonSequenceTypes::ZeroOrMoreItems);
      return result;
  }
  
  SequenceType::Ptr IfThenClause::staticType() const
  {
      const SequenceType::Ptr t1(m_operand2->staticType());
      const SequenceType::Ptr t2(m_operand3->staticType());
  
      return makeGenericSequenceType(t1->itemType() | t2->itemType(),
                                     t1->cardinality() | t2->cardinality());
  }
  
  ExpressionVisitorResult::Ptr IfThenClause::accept(const ExpressionVisitor::Ptr &visitor) const
  {
      return visitor->visit(this);
  }
  
  Expression::ID IfThenClause::id() const
  {
      return IDIfThenClause;
  }
  
  /*
  Expression::Properties IfThenClause::properties() const
  {
      return   m_operand1->properties()
             | m_operand2->properties()
             | m_operand3->properties()
             & (  Expression::RequiresFocus
                | Expression::IsEvaluated
                | Expression::DisableElimination);
  }
  */
  QT_END_NAMESPACE
  