bsls_nativestd.h

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/// @file bsls_nativestd.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bsls_nativestd.h                                                   -*-C++-*-
#ifndef INCLUDED_BSLS_NATIVESTD
#define INCLUDED_BSLS_NATIVESTD
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bsls_nativestd bsls_nativestd
/// @brief  Define the namespace `native_std` as an alias for `::std`.
/// @addtogroup bsl
/// @{
/// @addtogroup bsls
/// @{
/// @addtogroup bsls_nativestd
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bsls_nativestd-purpose"> Purpose</a>
/// * <a href="#bsls_nativestd-classes"> Classes </a>
/// * <a href="#bsls_nativestd-description"> Description </a>
///   * <a href="#bsls_nativestd-usage"> Usage </a>
///
/// # Purpose {#bsls_nativestd-purpose}
/// Define the namespace `native_std` as an alias for `::std`.
///
/// @deprecated  Use @ref std explicitly.
///
/// # Classes {#bsls_nativestd-classes}
///
///
/// # Description {#bsls_nativestd-description}
/// This component defines a namespace alias, `native_std`, that
/// serves as an alias for the `std` namespace.  The `bsl` package group
/// contains a Bloomberg implementation of the C++ standard library.  In the
/// past, this implementation supported using the preprocessor to replace `std`
/// with `bsl` and intercepting all standard library headers with BDE-provided
/// implementations.  When building in this bde-stl mode by defining
/// `BSL_OVERRIDES_STD`, there was still occasionally a need to refer to the
/// "real" `std` namespace, and that could be accomplished with the `native_std`
/// namespace.  This is no longer needed or used within BDE itself.
///
/// Note: It is safe to `#include` this header only if `std` is not yet defined
/// as a macro or if `BSL_DEFINED_NATIVE_STD` is already defined.  Any other
/// header that defines the `native_std` namespace should also define the
/// `BSL_DEFINED_NATIVE_STD` macro.  For more info on bde-stl mode, please see
/// `bos/bos+stdhdrs/doc/bos+stdhdrs.txt`.
///
/// ## Usage {#bsls_nativestd-usage}
///
///
/// In the following example we use the `native_std` prefix to access the native
/// implementation of `std::string`, even when the compilation is configured to
/// override the use of native STL types with Bloomberg provided STL types
/// (i.e., bde-stl mode, used by Bloomberg managed code):
/// @code
/// #include <bsls_nativestd.h>
/// #include <string>
///
/// std::string        s1;  // now always 'std::string'
/// native_std::string s2;  // always was 'std::string'
/// @endcode
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bsls
 * @{
 */
/** @addtogroup bsls_nativestd
 * @{
 */
 
#ifndef BSL_DEFINED_NATIVE_STD
 
# ifdef std
#   error "Cannot include bsls_nativestd.h when 'std' is a macro."
# endif
 
namespace std {
}
namespace native_std = ::std;
 
#endif  // ! defined(BSL_DEFINED_NATIVE_STD)
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2019 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 ----------------------------------
 
/** @} */
/** @} */
/** @} */