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/*
 *  R : A Computer Language for Statistical Data Analysis
 *  Copyright (C) 2000, 2026 The R Core Team.
 *
 *  This header file is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 2.1 of the License, or
 *  (at your option) any later version.
 *
 *  This file is part of R. R is distributed under the terms of the
 *  GNU General Public License, either Version 2, June 1991 or Version 3,
 *  June 2007. See doc/COPYRIGHTS for details of the copyright status of R.
 *
 *  This program 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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, a copy is available at
 *  https://www.R-project.org/Licenses/
 */

/* Included by R.h: API */

#ifndef R_EXT_BOOLEAN_H_
#define R_EXT_BOOLEAN_H_
#if !defined(R_INCLUDE_BOOLEAN_H) || R_INCLUDE_BOOLEAN_H

// NB: there is a version of this in Rmath.h0[.in]

#undef FALSE
#undef TRUE

/* Ensuure a 'bool' type is available.  We could use
   __bool_true_false_are_defined, 
   but that was declared obsolescent in C23.
*/
#if defined __STDC_VERSION__ && __STDC_VERSION__ > 202000L
// C23 so bool is a keyword
#elif defined __cplusplus
// part of C++ >= 11, which is all R supports.
#else
# include <stdbool.h>
// stdbool.h is C99, so available everywhere.
#endif

#include <Rconfig.h> /* for HAVE_ENUM_BASE_TYPE */
/*
  Setting the underlying aka base type is supported in C23, C++11 
  and some C compilers based on clang and some versions of GCC.
  What matters here is the C compiler used to build R.
 */
#ifdef  __cplusplus
extern "C" {
#endif
#ifdef HAVE_ENUM_BASE_TYPE
// Apple clang 17 warns even in C23 mode: gcc warns about #pragma clang
// LLVM clang no longer warns.
// Apple clang 21 no longer has that warning.
# if defined  __APPLE__ && defined __clang__ && __clang_major__ < 21
#  pragma clang diagnostic push
#  pragma clang diagnostic ignored "-Wfixed-enum-extension"
# endif

  typedef enum :int { FALSE = 0, TRUE } Rboolean;  // so NOT NA

# if defined  __APPLE__ && defined __clang__ && __clang_major__ < 21
#  pragma clang diagnostic pop
# endif
#else
    typedef enum { FALSE = 0, TRUE } Rboolean;  // so NOT NA
#endif
#ifdef  __cplusplus
}
#endif

#else
/* The Rbolean type is used in too many R headers to condition them
 * all.  However, people defining R_INCLUDE_BOOLEAN_H=0 should not be
 * using it in their own code, and its base type is expected to be int
 * (and guaranteed to be on most platforms as from R 4.5.0). */

    typedef Rboolean int;
#endif /* R_INCLUDE_BOOLEAN_H = 0 */
#endif /* R_EXT_BOOLEAN_H_ */