ArrayViewDumper.h

// -*- tab-width: 2; indent-tabs-mode: nil; coding: utf-8-with-signature -*-
//-----------------------------------------------------------------------------
// Copyright 2000-2026 CEA (www.cea.fr) IFPEN (www.ifpenergiesnouvelles.com)
// See the top-level COPYRIGHT file for details.
// SPDX-License-Identifier: Apache-2.0
//-----------------------------------------------------------------------------
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/* ArrayViewDumper.h                                           (C) 2000-2026 */
/*                                                                           */
/* Functions to dump values of Arccore array views (ArrayView, Span, ...)    */
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#ifndef ARCCORE_BASE_ARRAYVIEWDUMPER_H
#define ARCCORE_BASE_ARRAYVIEWDUMPER_H
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#include "arccore/base/ArccoreGlobal.h"
 
#include <iosfwd>
 
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namespace Arcane::Impl
{
 
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/*!
 * \brief Helper class to dump an array view on a stream.
 *
 * The method \a dumpArray() is templated on the stream type so we do not
 * need to include the header 'iostream' in this header. The goal is to reduce
 * compilation time. The user has to include 'iostream' if he needs to
 * dump the array.
 */
template <typename ViewType>
class ArrayViewDumper
{
 public:
 
  template <typename Stream> static void
  dumpArray(Stream& o, ViewType val, int max_print)
  {
    using size_type = typename ViewType::size_type;
    size_type n = val.size();
    if (max_print > 0 && n > max_print) {
      // Only displays the first (max_print/2) and the last (max_print/2)
      // otherwise if the array is very large it can generate enormous
      // output listings.
      size_type z = (max_print / 2);
      size_type z2 = n - z;
      o << "[0]=\"" << val[0] << '"';
      for (size_type i = 1; i < z; ++i)
        o << " [" << i << "]=\"" << val[i] << '"';
      o << " ... ... (skipping indexes " << z << " to " << z2 << " ) ... ... ";
      for (size_type i = (z2 + 1); i < n; ++i)
        o << " [" << i << "]=\"" << val[i] << '"';
    }
    else {
      for (size_type i = 0; i < n; ++i) {
        if (i != 0)
          o << ' ';
        o << "[" << i << "]=\"" << val[i] << '"';
      }
    }
  }
};
 
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} // namespace Arcane::Impl
 
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#endif