bslmf_arraytopointer.h

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/// @file bslmf_arraytopointer.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bslmf_arraytopointer.h                                             -*-C++-*-
#ifndef INCLUDED_BSLMF_ARRAYTOPOINTER
#define INCLUDED_BSLMF_ARRAYTOPOINTER
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bslmf_arraytopointer bslmf_arraytopointer
/// @brief  Provide a meta-function to convert array types to pointer types.
/// @addtogroup bsl
/// @{
/// @addtogroup bslmf
/// @{
/// @addtogroup bslmf_arraytopointer
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bslmf_arraytopointer-purpose"> Purpose</a>
/// * <a href="#bslmf_arraytopointer-classes"> Classes </a>
/// * <a href="#bslmf_arraytopointer-description"> Description </a>
///   * <a href="#bslmf_arraytopointer-usage"> Usage </a>
///
/// # Purpose {#bslmf_arraytopointer-purpose}
/// Provide a meta-function to convert array types to pointer types.
///
/// # Classes {#bslmf_arraytopointer-classes}
///
/// -  bslmf::ArrayToPointer: convert an array type to a pointer type
/// -  bslmf::ArrayToConstPointer: convert an array type to a `const` pointer type
///
/// @see  bslmf_isarray, bslmf_forwardingtype
///
/// # Description {#bslmf_arraytopointer-description}
/// This component provides a meta function for converting array
/// types to pointer types.  The utility is generally used for in templates that
/// require forwarding or storage of arguments that are passed a arrays(e.g.,
/// "string literals").  For non array types, the type is left unmodified.  Note
/// that `bslmf::ArrayToPointer` and `bslmf::ArrayToConstPointer` retain the CV
/// qualifiers of the original type.  In other words, if the original array type
/// was `const` or `volatile`, or `const volatile`, the converted pointer type
/// will also be `const`, `volatile`, or `const volatile` respectively.
///
/// When an explicit const pointer pointer type is needed(such as when accepting
/// as argument, then `bslmf::ArrayToConstPointer` should be used.
///
/// ## Usage {#bslmf_arraytopointer-usage}
///
///
/// For example:
/// @code
/// assert(1 == bsl::is_same<bslmf::ArrayToPointer<int[5]>::Type
///                         , int *>::value);
/// assert(1 == bsl::is_same<bslmf::ArrayToPointer<int *>::Type
///                         , int *>::value);
/// assert(0 == bsl::is_same<bslmf::ArrayToPointer<int (*)[5]>::Type]
///                         , int **>::value);
/// @endcode
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bslmf
 * @{
 */
/** @addtogroup bslmf_arraytopointer
 * @{
 */
 
#include <bslscm_version.h>
 
#include <cstddef>       // for 'std::size_t'
 
 
 
namespace bslmf {
 
                            // =====================
                            // struct ArrayToPointer
                            // =====================
 
template <class t_TYPE, class t_ORIGINAL_TYPE>
struct ArrayToPointer_Imp;
 
template <class t_TYPE>
struct ArrayToPointer {
    typedef typename ArrayToPointer_Imp<t_TYPE, t_TYPE>::Type Type;
};
 
template <class t_TYPE>
struct ArrayToPointer<t_TYPE&> {
    typedef typename ArrayToPointer_Imp<t_TYPE, t_TYPE&>::Type Type;
};
 
                          // ==========================
                          // struct ArrayToConstPointer
                          // ==========================
 
template <class t_TYPE>
struct ArrayToConstPointer {
    typedef typename ArrayToPointer_Imp<const t_TYPE, t_TYPE>::Type Type;
};
 
template <class t_TYPE>
struct ArrayToConstPointer<t_TYPE&> {
    typedef typename ArrayToPointer_Imp<const t_TYPE, t_TYPE&>::Type Type;
};
 
                         // =========================
                         // struct ArrayToPointer_Imp
                         // =========================
 
template <class t_TYPE, class t_ORIGINAL_TYPE>
struct ArrayToPointer_Imp {
    typedef t_ORIGINAL_TYPE Type;
};
 
template <class t_TYPE, std::size_t t_NUM_ELEMENTS, class t_UNUSED>
struct ArrayToPointer_Imp<t_TYPE[t_NUM_ELEMENTS], t_UNUSED> {
    typedef t_TYPE *Type;
};
 
template <class t_TYPE, class t_UNUSED>
struct ArrayToPointer_Imp<t_TYPE[], t_UNUSED> {
    typedef t_TYPE *Type;
};
 
}  // close package namespace
 
#ifndef BDE_OPENSOURCE_PUBLICATION  // BACKWARD_COMPATIBILITY
// ============================================================================
//                           BACKWARD COMPATIBILITY
// ============================================================================
 
#ifdef bslmf_ArrayToConstPointer
#undef bslmf_ArrayToConstPointer
#endif
/// This alias is defined for backward compatibility.
#define bslmf_ArrayToConstPointer bslmf::ArrayToConstPointer
 
#ifdef bslmf_ArrayToPointer
#undef bslmf_ArrayToPointer
#endif
/// This alias is defined for backward compatibility.
#define bslmf_ArrayToPointer bslmf::ArrayToPointer
#endif  // BDE_OPENSOURCE_PUBLICATION -- BACKWARD_COMPATIBILITY
 
 
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2013 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */