1///////////////////////////////////////////////////////////////////////////
2//
3// Copyright (c) 2012, Industrial Light & Magic, a division of Lucas
4// Digital Ltd. LLC
5//
6// All rights reserved.
7//
8// Redistribution and use in source and binary forms, with or without
9// modification, are permitted provided that the following conditions are
10// met:
11// * Redistributions of source code must retain the above copyright
12// notice, this list of conditions and the following disclaimer.
13// * Redistributions in binary form must reproduce the above
14// copyright notice, this list of conditions and the following disclaimer
15// in the documentation and/or other materials provided with the
16// distribution.
17// * Neither the name of Industrial Light & Magic nor the names of
18// its contributors may be used to endorse or promote products derived
19// from this software without specific prior written permission.
20//
21// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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30// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32//
33///////////////////////////////////////////////////////////////////////////
34
35#ifndef INCLUDED_IEXNAMESPACE_H
36#define INCLUDED_IEXNAMESPACE_H
37
38//
39// The purpose of this file is to make it possible to specify an
40// IEX_INTERNAL_NAMESPACE as a preprocessor definition and have all of the
41// Iex symbols defined within that namespace rather than the standard
42// Iex namespace. Those symbols are made available to client code through
43// the IEX_NAMESPACE in addition to the IEX_INTERNAL_NAMESPACE.
44//
45// To ensure source code compatibility, the IEX_NAMESPACE defaults to Iex
46// and then "using namespace IEX_INTERNAL_NAMESPACE;" brings all of the
47// declarations from the IEX_INTERNAL_NAMESPACE into the IEX_NAMESPACE. This
48// means that client code can continue to use syntax like Iex::BaseExc, but
49// at link time it will resolve to a mangled symbol based on the
50// IEX_INTERNAL_NAMESPACE.
51//
52// As an example, if one needed to build against a newer version of Iex and
53// have it run alongside an older version in the same application, it is now
54// possible to use an internal namespace to prevent collisions between the
55// older versions of Iex symbols and the newer ones. To do this, the
56// following could be defined at build time:
57//
58// IEX_INTERNAL_NAMESPACE = Iex_v2
59//
60// This means that declarations inside Iex headers look like this (after the
61// preprocessor has done its work):
62//
63// namespace Iex_v2 {
64// ...
65// class declarations
66// ...
67// }
68//
69// namespace Iex {
70// using namespace Iex_v2;
71// }
72//
73
74//
75// Open Source version of this file pulls in the IlmBaseConfig.h file
76// for the configure time options.
77//
78#include "IlmBaseConfig.h"
79
80#ifndef IEX_NAMESPACE
81#define IEX_NAMESPACE Iex
82#endif
83
84#ifndef IEX_INTERNAL_NAMESPACE
85#define IEX_INTERNAL_NAMESPACE IEX_NAMESPACE
86#endif
87
88//
89// We need to be sure that we import the internal namespace into the public one.
90// To do this, we use the small bit of code below which initially defines
91// IEX_INTERNAL_NAMESPACE (so it can be referenced) and then defines
92// IEX_NAMESPACE and pulls the internal symbols into the public namespace.
93//
94
95namespace IEX_INTERNAL_NAMESPACE {}
96namespace IEX_NAMESPACE {
97 using namespace IEX_INTERNAL_NAMESPACE;
98}
99
100//
101// There are identical pairs of HEADER/SOURCE ENTER/EXIT macros so that
102// future extension to the namespace mechanism is possible without changing
103// project source code.
104//
105
106#define IEX_INTERNAL_NAMESPACE_HEADER_ENTER namespace IEX_INTERNAL_NAMESPACE {
107#define IEX_INTERNAL_NAMESPACE_HEADER_EXIT }
108
109#define IEX_INTERNAL_NAMESPACE_SOURCE_ENTER namespace IEX_INTERNAL_NAMESPACE {
110#define IEX_INTERNAL_NAMESPACE_SOURCE_EXIT }
111
112#endif // INCLUDED_IEXNAMESPACE_H
113

source code of include/OpenEXR/IexNamespace.h