bsltf_convertiblevaluewrapper.h

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/// @file bsltf_convertiblevaluewrapper.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bsltf_convertiblevaluewrapper.h                                    -*-C++-*-
#ifndef INCLUDED_BSLTF_CONVERTIBLEVALUEWRAPPER
#define INCLUDED_BSLTF_CONVERTIBLEVALUEWRAPPER
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bsltf_convertiblevaluewrapper bsltf_convertiblevaluewrapper
/// @brief  Provide a wrapper class, convertible to a supplied value.
/// @addtogroup bsl
/// @{
/// @addtogroup bsltf
/// @{
/// @addtogroup bsltf_convertiblevaluewrapper
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bsltf_convertiblevaluewrapper-purpose"> Purpose</a>
/// * <a href="#bsltf_convertiblevaluewrapper-classes"> Classes </a>
/// * <a href="#bsltf_convertiblevaluewrapper-description"> Description </a>
///   * <a href="#bsltf_convertiblevaluewrapper-usage"> Usage </a>
///     * <a href="#bsltf_convertiblevaluewrapper-example-1-tbd"> Example 1: TBD </a>
///
/// # Purpose {#bsltf_convertiblevaluewrapper-purpose}
/// Provide a wrapper class, convertible to a supplied value.
///
/// # Classes {#bsltf_convertiblevaluewrapper-classes}
///
/// -   bsltf::ConvertibleValueWrapper: wrapper of a value-semantic class
///
/// @see  bsltf_templatetestfacility
///
/// # Description {#bsltf_convertiblevaluewrapper-description}
/// This component provides a `struct` that holds an object of a
/// template parameter type, and provides implicit conversions to, and from,
/// that type.  A `bsltf::ConvertibleValueWrapper` facilitates testing of
/// function templates whose contract requires a type that is "convertible to
/// the specified type".  It also ensures that this uses up the one user-defined
/// conversion in permitted in the conversion sequence, rather than accidentally
/// relying on a built-in conversion such as type promotion.
///
/// ## Usage {#bsltf_convertiblevaluewrapper-usage}
///
///
/// This section illustrates intended use of this component.
///
/// ### Example 1: TBD {#bsltf_convertiblevaluewrapper-example-1-tbd}
///
///
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bsltf
 * @{
 */
/** @addtogroup bsltf_convertiblevaluewrapper
 * @{
 */
 
#include <bslscm_version.h>
 
 
 
namespace bsltf {
 
                       // =============================
                       // class ConvertibleValueWrapper
                       // =============================
 
/// This class provides a wrapper around an object of the specified
/// (template parameter) `TYPE`.  `TYPE` shall be CopyConstructible.  If
/// `TYPE` is a value-semantic type, then this class will also be value
/// semantic.  Objects of this type are implicitly convertible to and from
/// objects of the specified `TYPE`.
///
/// See @ref bsltf_convertiblevaluewrapper 
template <class TYPE>
struct ConvertibleValueWrapper {
 
  private:
    // DATA
    TYPE d_value;
 
  public:
    // CREATORS
 
    /// Create an object wrapping the specified `value`.
    ConvertibleValueWrapper(const TYPE& value);                     // IMPLICIT
 
    // MANIPULATORS
 
    /// Return a reference to the (modifiable) wrapped value.
    operator       TYPE&();
 
    // ACCESSORS
 
    /// Return a reference to the (non-modifiable) wrapped value.
    operator const TYPE&() const;
};
 
 
// ============================================================================
//                  INLINE AND TEMPLATE FUNCTION IMPLEMENTATIONS
// ============================================================================
 
 
                       // -----------------------------
                       // class ConvertibleValueWrapper
                       // -----------------------------
 
// CREATORS
template <class TYPE>
inline
ConvertibleValueWrapper<TYPE>::ConvertibleValueWrapper(const TYPE& value)
: d_value(value)
{
}
 
template <class TYPE>
inline
ConvertibleValueWrapper<TYPE>::operator TYPE&()
{
    return d_value;
}
 
// ACCESSORS
template <class TYPE>
inline
ConvertibleValueWrapper<TYPE>::operator const TYPE&() const
{
    return d_value;
}
 
}  // close package namespace
 
 
#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 ----------------------------------
 
/** @} */
/** @} */
/** @} */