ValueHolder.h

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// # ValueHolder.h: A holder object for the standard Casacore data types
// # Copyright (C) 2005
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 of the License, or (at your
// # option) any later version.
// #
// # This library 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.  See the GNU Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef CASA_VALUEHOLDER_H
#define CASA_VALUEHOLDER_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/Containers/ValueHolderRep.h>
#include <casacore/casa/Arrays/Array.h>
#include <memory>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// <summary>
// A holder for a value of any basic Casacore data type.
// </summary>
 
// <use visibility=export>
// <reviewed reviewer="" date="" tests="tValueHolder">
// </reviewed>
 
// <synopsis>
// Class ValueHolder is meant to be used for holding a single Casacore value.
// The value can be  scalar or an array of any basic type (including complex
// and string). Also a Record value is possible.
// In this way varying typed data (e.g. the result of getCell in the table DO)
// can be packed in a strongly typed variable.
// <br>All unsigned integer type values are kept as signed 32-bit integers
// because scripting languages usually only support those types.
//
// ValueHolder is an envelope class that holds a counted-referenced letter
// object <linkto class=ValueHolderRep>ValueHolderRep</linkto>.
// </synopsis>
 
// <motivation>
// This class comes handy in passing arbitrary values from a DO to
// its environment.
// </motivation>
 
class ValueHolder {
 public:
  // Construct a null object.
  ValueHolder() {}
 
  // Create the object for the given value.
  // <group>
  explicit ValueHolder(Bool value);
  explicit ValueHolder(uChar value);
  explicit ValueHolder(Short value);
  explicit ValueHolder(uShort value);
  explicit ValueHolder(Int value);
  explicit ValueHolder(uInt value);
  explicit ValueHolder(Int64 value);
  explicit ValueHolder(Float value);
  explicit ValueHolder(Double value);
  explicit ValueHolder(const Complex& value);
  explicit ValueHolder(const DComplex& value);
  explicit ValueHolder(const Char* value);
  explicit ValueHolder(const String& value);
  explicit ValueHolder(const Array<Bool>& value);
  explicit ValueHolder(const Array<uChar>& value);
  explicit ValueHolder(const Array<Short>& value);
  explicit ValueHolder(const Array<uShort>& value);
  explicit ValueHolder(const Array<Int>& value);
  explicit ValueHolder(const Array<uInt>& value);
  explicit ValueHolder(const Array<Int64>& value);
  explicit ValueHolder(const Array<Float>& value);
  explicit ValueHolder(const Array<Double>& value);
  explicit ValueHolder(const Array<Complex>& value);
  explicit ValueHolder(const Array<DComplex>& value);
  explicit ValueHolder(const Array<String>& value);
  explicit ValueHolder(const Record& value);
  // </group>
 
  // Create an empty N-dim array (gets type TpOther).
  ValueHolder(uInt ndim, Bool dummy);
 
  // Create a ValueHolder from a ValueHolderRep.
  // It takes over the pointer and deletes it in the destructor.
  explicit ValueHolder(ValueHolderRep* rep) : itsRep(rep) {}
 
  // Copy constructor (reference semantics).
  ValueHolder(const ValueHolder&);
 
  // Destructor.
  ~ValueHolder() {}
 
  // Assignment (reference semantics).
  ValueHolder& operator=(const ValueHolder&);
 
  // Is this a null object?
  Bool isNull() const { return !itsRep; }
 
  // Get the data type (as defined in DataType.h).
  // Note that TpOther is returned for an empty untyped array.
  DataType dataType() const;
 
  // Get the value.
  // If possible, it converts the data as needed.
  // <group>
  Bool asBool() const;
  uChar asuChar() const;
  Short asShort() const;
  uShort asuShort() const;
  Int asInt() const;
  uInt asuInt() const;
  Int64 asInt64() const;
  Float asFloat() const;
  Double asDouble() const;
  Complex asComplex() const;
  DComplex asDComplex() const;
  const String& asString() const;
  const Array<Bool> asArrayBool() const;
  const Array<uChar> asArrayuChar() const;
  const Array<Short> asArrayShort() const;
  const Array<uShort> asArrayuShort() const;
  const Array<Int> asArrayInt() const;
  const Array<uInt> asArrayuInt() const;
  const Array<Int64> asArrayInt64() const;
  const Array<Float> asArrayFloat() const;
  const Array<Double> asArrayDouble() const;
  const Array<Complex> asArrayComplex() const;
  const Array<DComplex> asArrayDComplex() const;
  const Array<String> asArrayString() const;
  const Record& asRecord() const;
  // </group>
 
  // Get the data in a way useful for templates.
  // If possible, it converts the the data as needed.
  // <group>
  void getValue(Bool& value) const { value = asBool(); }
  void getValue(uChar& value) const { value = asuChar(); }
  void getValue(Short& value) const { value = asShort(); }
  void getValue(uShort& value) const { value = asuShort(); }
  void getValue(Int& value) const { value = asInt(); }
  void getValue(uInt& value) const { value = asuInt(); }
  void getValue(Int64& value) const { value = asInt64(); }
  void getValue(Float& value) const { value = asFloat(); }
  void getValue(Double& value) const { value = asDouble(); }
  void getValue(Complex& value) const { value = asComplex(); }
  void getValue(DComplex& value) const { value = asDComplex(); }
  void getValue(String& value) const { value = asString(); }
  void getValue(Array<Bool>& value) const { value.reference(asArrayBool()); }
  void getValue(Array<uChar>& value) const { value.reference(asArrayuChar()); }
  void getValue(Array<Short>& value) const { value.reference(asArrayShort()); }
  void getValue(Array<uShort>& value) const { value.reference(asArrayuShort()); }
  void getValue(Array<Int>& value) const { value.reference(asArrayInt()); }
  void getValue(Array<uInt>& value) const { value.reference(asArrayuInt()); }
  void getValue(Array<Int64>& value) const { value.reference(asArrayInt64()); }
  void getValue(Array<Float>& value) const { value.reference(asArrayFloat()); }
  void getValue(Array<Double>& value) const { value.reference(asArrayDouble()); }
  void getValue(Array<Complex>& value) const { value.reference(asArrayComplex()); }
  void getValue(Array<DComplex>& value) const { value.reference(asArrayDComplex()); }
  void getValue(Array<String>& value) const { value.reference(asArrayString()); }
  // </group>
 
  // Put the value as a field in a record.
  void toRecord(Record&, const RecordFieldId&) const;
 
  // Construct the object from the value in a record.
  static ValueHolder fromRecord(const Record&, const RecordFieldId&);
 
  // Compare two ValueHolder objects.
  // They must have the same data type.
  bool operator<(const ValueHolder& right) const { return itsRep->operator<(*right.itsRep); }
 
  // Write the ValueHolder to an output stream.
  // Arrays are written as normal arrays using ArrayIO.h.
  friend std::ostream& operator<<(std::ostream& os, const ValueHolder& vh) {
    return vh.itsRep->write(os);
  }
 
 private:
  std::shared_ptr<ValueHolderRep> itsRep;
};
 
inline DataType ValueHolder::dataType() const { return itsRep->dataType(); }
inline void ValueHolder::toRecord(Record& rec, const RecordFieldId& id) const {
  return itsRep->toRecord(rec, id);
}
inline ValueHolder ValueHolder::fromRecord(const Record& rec, const RecordFieldId& id) {
  return ValueHolder(ValueHolderRep::fromRecord(rec, id));
}
inline Bool ValueHolder::asBool() const { return itsRep->asBool(); }
inline uChar ValueHolder::asuChar() const { return itsRep->asuChar(); }
inline Short ValueHolder::asShort() const { return itsRep->asShort(); }
inline uShort ValueHolder::asuShort() const { return itsRep->asuShort(); }
inline Int ValueHolder::asInt() const { return itsRep->asInt(); }
inline uInt ValueHolder::asuInt() const { return itsRep->asuInt(); }
inline Int64 ValueHolder::asInt64() const { return itsRep->asInt64(); }
inline Float ValueHolder::asFloat() const { return itsRep->asFloat(); }
inline Double ValueHolder::asDouble() const { return itsRep->asDouble(); }
inline Complex ValueHolder::asComplex() const { return itsRep->asComplex(); }
inline DComplex ValueHolder::asDComplex() const { return itsRep->asDComplex(); }
inline const String& ValueHolder::asString() const { return itsRep->asString(); }
inline const Array<Bool> ValueHolder::asArrayBool() const { return itsRep->asArrayBool(); }
inline const Array<uChar> ValueHolder::asArrayuChar() const { return itsRep->asArrayuChar(); }
inline const Array<Short> ValueHolder::asArrayShort() const { return itsRep->asArrayShort(); }
inline const Array<uShort> ValueHolder::asArrayuShort() const { return itsRep->asArrayuShort(); }
inline const Array<Int> ValueHolder::asArrayInt() const { return itsRep->asArrayInt(); }
inline const Array<uInt> ValueHolder::asArrayuInt() const { return itsRep->asArrayuInt(); }
inline const Array<Int64> ValueHolder::asArrayInt64() const { return itsRep->asArrayInt64(); }
inline const Array<Float> ValueHolder::asArrayFloat() const { return itsRep->asArrayFloat(); }
inline const Array<Double> ValueHolder::asArrayDouble() const { return itsRep->asArrayDouble(); }
inline const Array<Complex> ValueHolder::asArrayComplex() const { return itsRep->asArrayComplex(); }
inline const Array<DComplex> ValueHolder::asArrayDComplex() const {
  return itsRep->asArrayDComplex();
}
inline const Array<String> ValueHolder::asArrayString() const { return itsRep->asArrayString(); }
inline const Record& ValueHolder::asRecord() const { return itsRep->asRecord(); }
 
}  // namespace casacore
 
#endif