TaQLStyle.h

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//# TaQLStyle.h: Class with static members defining the TaQL style
//# Copyright (C) 2006
//# 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: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
//#                        Charlottesville, VA 22903-2475 USA
//#
//# $Id$

#ifndef TABLES_TAQLSTYLE_H
#define TABLES_TAQLSTYLE_H

//# Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/BasicSL/String.h>
#include <casacore/casa/stdmap.h>

namespace casacore { //# NAMESPACE CASACORE - BEGIN

// <summary>
// Class with static members defining the TaQL style.
// </summary>

// <use visibility=local>

// <reviewed reviewer="" date="" tests="">
// </reviewed>

// <synopsis>
// Originally TaQL was developed to use the Glish style of indexing.
// This meant 1-based indices, axes in Fortran order, and end is inclusive
// in start:end.
// On the other hand the Python style is the opposite.
// In order to let the user choose between styles, one can define the
// style in a TaQL command.
// The default style is Glish.
//
// The class is also used to tell the TaQL execution engine if timings
// or tracing of the various parts of the TaQL command need to be done.
//
// Finally it is possible to define synonyms for UDF library names.
// For example, 'derivedmscal' is a lot to type, so a synonym 'mscal'
// (or even 'mc') can be defined for it.
// </synopsis> 

class TaQLStyle
{
public:
  // Default style is Glish and no timing/tracing.
  explicit TaQLStyle (uInt origin=1);

  // Reset to the default Glish style and no timing/tracing.
  void reset();

  // Set the style according to the (case-insensitive) value.
  // Possible values are Glish, Python, Base0, Base1, FortranOrder, Corder,
  // InclEnd, and ExclEnd.
  void set (const String& value);

  // Define a UDF library name synonym.
  // The synonym name is always converted to lowercase because TaQL always
  // uses lowercase to lookup functions. The library name kept as is making
  // it possible to use a library containing uppercase characters.
  // If the synonym already exists, it is redefined.
  void defineSynonym (const String& synonym, const String& udfLibName);

  // Set a synonym using a command like 'synonym = udflibname'.
  void defineSynonym (const String& command);

  // Find the UDF library name belonging to a synonym.
  // If undefined, the synonym itself is returned.
  String findSynonym (const String& synonym) const;

  // Get the various style values.
  // <group>
  uInt origin() const
    { return itsOrigin; }
  Bool isEndExcl() const
    { return itsEndExcl; }
  Bool isCOrder() const
    { return itsCOrder; }
  // </group>

  // Set if timing needs to be done.
  void setTiming (Bool doTiming)
    { itsDoTiming = doTiming; }

  // Should timing be done?
  Bool doTiming() const
    { return itsDoTiming; }

  // Set if tracing needs to be done.
  void setTracing (Bool doTracing)
    { itsDoTracing = doTracing; }

  // Should tracing be done?
  Bool doTracing() const
    { return itsDoTracing; }

private:
  uInt itsOrigin;
  Bool itsEndExcl;
  Bool itsCOrder;
  Bool itsDoTiming;
  Bool itsDoTracing;
  std::map<String,String> itsUDFLibNameMap;
};


} //# NAMESPACE CASACORE - END

#endif