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//
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#ifndef IMPALA_EXPRS_NULL_LITERAL_H_
#define IMPALA_EXPRS_NULL_LITERAL_H_

#include "exprs/scalar-expr.h"

namespace impala {

using impala_udf::FunctionContext;
using impala_udf::BooleanVal;
using impala_udf::TinyIntVal;
using impala_udf::SmallIntVal;
using impala_udf::IntVal;
using impala_udf::BigIntVal;
using impala_udf::FloatVal;
using impala_udf::DoubleVal;
using impala_udf::TimestampVal;
using impala_udf::StringVal;
using impala_udf::DecimalVal;
using impala_udf::DateVal;

class TExprNode;

class NullLiteral: public ScalarExpr {
 public:
  virtual bool IsLiteral() const override { return true; }
  virtual Status GetCodegendComputeFnImpl(LlvmCodeGen* codegen, llvm::Function** fn)
      override WARN_UNUSED_RESULT;
  virtual std::string DebugString() const override;

  /// Constructor for test.
  NullLiteral(PrimitiveType type) : ScalarExpr(type, true) { }

  static const char* LLVM_CLASS_NAME;

 protected:
  friend class ScalarExpr;
  friend class ScalarExprEvaluator;

  NullLiteral(const TExprNode& node) : ScalarExpr(node) { }

  GENERATE_GET_VAL_INTERPRETED_OVERRIDES_FOR_ALL_SCALAR_TYPES
  virtual CollectionVal GetCollectionValInterpreted(
      ScalarExprEvaluator*, const TupleRow*) const override;
};

}

#endif