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<h1 class="page">Boost Macros</h1>
<div id="preamble">
<div class="sectionbody">
<div class="paragraph">
<p>Boost provides many useful macros that help with configuration, debugging, portability, and convenience when working with the libraries.</p>
</div>
<div class="paragraph">
<p>There are thousands of defined macros (refer to the <a href="https://www.boost.org/doc/libs/latest/libs/config/doc/html/boost_config/boost_macro_reference.html">Boost Macro Reference</a>). However, here are some of the most commonly used, and some sample code showing how to work them into your code.</p>
</div>
<div class="ulist square">
<ul class="square">
<li>
<p><a href="#_library_inclusion_and_linking">Library Inclusion and Linking</a></p>
</li>
<li>
<p><a href="#_configuration_and_compiler_detection">Configuration and Compiler Detection</a></p>
</li>
<li>
<p><a href="#_debugging_and_assertions">Debugging and Assertions</a></p>
</li>
<li>
<p><a href="#_preprocessor_utilities">Preprocessor Utilities</a></p>
</li>
<li>
<p><a href="#_cross_platform_compatibility">Cross-Platform Compatibility</a></p>
</li>
<li>
<p><a href="#_threading_and_synchronization">Threading and Synchronization</a></p>
</li>
<li>
<p><a href="#_exception_handling">Exception Handling</a></p>
</li>
</ul>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_library_inclusion_and_linking"><a class="anchor" href="#_library_inclusion_and_linking"></a>Library Inclusion and Linking</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_ALL_NO_LIB</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Disables automatic linking for all Boost libraries.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_LIB_DIAGNOSTIC</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Enables diagnostic output for automatic linking.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_INCLUDE_LIBRARIES</code>(libs&#8230;&#8203;)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Used to specify which libraries should be included when using <a href="https://www.bfgroup.xyz/b2/">B2</a>.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_ALL_DYN_LINK</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Forces all Boost libraries to be linked dynamically.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_example"><a class="anchor" href="#_example"></a>Example</h3>
<div class="paragraph">
<p>The <code>BOOST_ALL_NO_LIB</code> macro prevents automatic linking of Boost libraries.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#define BOOST_ALL_NO_LIB // Disable auto-linking
#include &lt;boost/filesystem.hpp&gt;
#include &lt;iostream&gt;
int main() {
std::cout &lt;&lt; "Boost Filesystem is included, but auto-linking is disabled.\n";
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_configuration_and_compiler_detection"><a class="anchor" href="#_configuration_and_compiler_detection"></a>Configuration and Compiler Detection</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_VERSION</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defines the Boost version as an integer (for example, 107800 for Boost 1.78.0).</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_PLATFORM</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Identifies the platform (for example, Windows, Linux).</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_COMPILER</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Identifies the compiler in use (for example, gcc, msvc).</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_STDLIB</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Identifies the standard library (for example, libstdc++, msvc).</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_SP_USE_QUICK_ALLOCATOR</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Optimizes memory allocation for <code>shared_ptr</code>.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_NO_CXX11_SMART_PTR</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defined if C++11 <code>std::shared_ptr</code> and <code>std::unique_ptr</code> are not available, so Boost&#8217;s smart pointers are used as a fallback.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_STATIC_CONSTANT</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defines compile-time constants in a way that is compatible with older C++ versions, so ensures compatibility with pre-C++11 compilers.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_FILESYSTEM_VERSION</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defines the version of the <a href="https://www.boost.org/libs/filesystem">Boost.Filesystem</a> library being used, to ensure compatibility between different versions of that library.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_NO_CXX11_LAMBDAS</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defined if C++11 lambda expressions are not available, so allows for providing alternative function objects for compatibility.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_FILESYSTEM_NO_DEPRECATED</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Disables deprecated features in <a href="https://www.boost.org/libs/filesystem">Boost.Filesystem</a>.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_examples"><a class="anchor" href="#_examples"></a>Examples</h3>
<div class="paragraph">
<p>The <code>BOOST_STDLIB</code> macro is part of <a href="https://www.boost.org/libs/config">Boost.Config</a> and identifies the standard library implementation being used (for example, GNU libstdc++, Microsoft STL, or libc++). This is useful when writing code that needs to adapt to different standard library behaviors. <code>BOOST_STDLIB</code> expands to a string representing the detected standard library.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;boost/config.hpp&gt;
#include &lt;iostream&gt;
int main() {
std::cout &lt;&lt; "Detected Standard Library: " &lt;&lt; BOOST_STDLIB &lt;&lt; std::endl;
#ifdef BOOST_LIBSTD_GNU
std::cout &lt;&lt; "Using GNU libstdc++" &lt;&lt; std::endl;
#elif defined(BOOST_LIBSTD_MSVC)
std::cout &lt;&lt; "Using Microsoft STL (MSVC Standard Library)" &lt;&lt; std::endl;
#elif defined(BOOST_LIBSTD_LIBCXX)
std::cout &lt;&lt; "Using libc++ (Clang Standard Library)" &lt;&lt; std::endl;
#else
std::cout &lt;&lt; "Using an unknown or unsupported standard library" &lt;&lt; std::endl;
#endif
return 0;
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using <code>BOOST_PLATFORM</code>, <code>BOOST_COMPILER</code>, and <code>BOOST_STDLIB</code> for diagnostics by identifing the system&#8217;s platform, compiler, and standard library.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;iostream&gt;
#include &lt;boost/config.hpp&gt;
int main() {
std::cout &lt;&lt; "Platform: " &lt;&lt; BOOST_PLATFORM &lt;&lt; std::endl;
std::cout &lt;&lt; "Compiler: " &lt;&lt; BOOST_COMPILER &lt;&lt; std::endl;
std::cout &lt;&lt; "Standard Library: " &lt;&lt; BOOST_STDLIB &lt;&lt; std::endl;
return 0;
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using <code>BOOST_VERSION</code> to ensure version compatibility when using Boost.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;iostream&gt;
#include &lt;boost/version.hpp&gt;
int main() {
std::cout &lt;&lt; "Boost version: "
&lt;&lt; (BOOST_VERSION / 100000) &lt;&lt; "." // Major version
&lt;&lt; (BOOST_VERSION / 100 % 1000) &lt;&lt; "." // Minor version
&lt;&lt; (BOOST_VERSION % 100) &lt;&lt; std::endl; // Patch version
return 0;
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using <code>BOOST_SP_USE_QUICK_ALLOCATOR</code> to optimize <code>shared_ptr</code>.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#define BOOST_SP_USE_QUICK_ALLOCATOR // Define before including Boost.SmartPtr
#include &lt;boost/smart_ptr.hpp&gt;
#include &lt;iostream&gt;
int main() {
boost::shared_ptr&lt;int&gt; ptr1(new int(42));
boost::shared_ptr&lt;int&gt; ptr2 = ptr1;
std::cout &lt;&lt; "Shared pointer value: " &lt;&lt; *ptr1 &lt;&lt; std::endl;
return 0;
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_debugging_and_assertions"><a class="anchor" href="#_debugging_and_assertions"></a>Debugging and Assertions</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_ASSERT</code>(expr)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Asserts an expression, throwing an error in debug builds.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_STATIC_ASSERT</code>(expr)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Performs a compile-time assertion.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_STATIC_ASSERT_MSG</code>(expr, msg)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Performs a compile-time assertion, with an added message.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_VERIFY</code>(expr)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Like <code>BOOST_ASSERT</code>, but always evaluates the expression, even in release mode.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_ENABLE_ASSERT_HANDLER</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Enables a custom assertion handler.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_ASIO_ENABLE_HANDLER_TRACKING</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Enables the debugging of handlers when using <a href="https://www.boost.org/libs/asio">Boost.Asio</a>.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_examples_2"><a class="anchor" href="#_examples_2"></a>Examples</h3>
<div class="paragraph">
<p>Using <code>BOOST_ASSERT</code>, <code>BOOST_STATIC_ASSERT</code>, and <code>BOOST_VERIFY</code> for debugging.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;boost/assert.hpp&gt;
#include &lt;boost/static_assert.hpp&gt;
#include &lt;iostream&gt;
void process(int value) {
BOOST_ASSERT(value &gt; 0 &amp;&amp; "Value must be positive"); // Runtime assertion
}
int main() {
BOOST_STATIC_ASSERT(sizeof(int) == 4); // Compile-time assertion
int x = 10;
BOOST_VERIFY(x != 0); // Always checks in release mode
process(-1); // Will trigger an assertion failure
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using <code>BOOST_ASIO_ENABLE_HANDLER_TRACKING</code> to help debug asynchronous operations by tracking handlers.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#define BOOST_ASIO_ENABLE_HANDLER_TRACKING // Enable debugging before including Boost.Asio
#include &lt;boost/asio.hpp&gt;
#include &lt;iostream&gt;
int main() {
boost::asio::io_context io;
std::cout &lt;&lt; "Boost.Asio handler tracking enabled!\n";
return 0;
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_preprocessor_utilities"><a class="anchor" href="#_preprocessor_utilities"></a>Preprocessor Utilities</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_PP_REPEAT</code>(count, macro, data)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Repeats a macro expansion a specified number of times.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_PP_IF</code>(cond, then, else)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Implements an if-like construct at preprocessing time.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_PP_ENUM_PARAMS</code>(count, param)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Expands into a comma-separated list of parameters.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_example_2"><a class="anchor" href="#_example_2"></a>Example</h3>
<div class="paragraph">
<p>Using <code>BOOST_PP_REPEAT</code> to generate repeated code.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;boost/preprocessor/repetition/repeat.hpp&gt;
#include &lt;iostream&gt;
#define PRINT_N(z, n, text) std::cout &lt;&lt; text &lt;&lt; " " &lt;&lt; n &lt;&lt; "\n";
int main() {
BOOST_PP_REPEAT(5, PRINT_N, "Iteration");
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_cross_platform_compatibility"><a class="anchor" href="#_cross_platform_compatibility"></a>Cross-Platform Compatibility</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_WINDOWS</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defined when compiling on Windows.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_LINUX</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defined when compiling on Linux.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_UNIX</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Defined when compiling on a Unix-like system.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_LITTLE_ENDIAN</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Define when the system is byte-order little-endian.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_BIG_ENDIAN</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Define when the system is byte-order big-endian.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_examples_3"><a class="anchor" href="#_examples_3"></a>Examples</h3>
<div class="paragraph">
<p>Using <code>BOOST_WINDOWS</code>, <code>BOOST_LINUX</code>, and <code>BOOST_UNIX</code> for platform-specific code.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;iostream&gt;
int main() {
#ifdef BOOST_WINDOWS
std::cout &lt;&lt; "Running on Windows\n";
#elif defined(BOOST_LINUX)
std::cout &lt;&lt; "Running on Linux\n";
#elif defined(BOOST_UNIX)
std::cout &lt;&lt; "Running on a Unix-like system\n";
#else
std::cout &lt;&lt; "Unknown platform\n";
#endif
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using Using BOOST_LITTLE_ENDIAN and BOOST_BIG_ENDIAN for proper handling of byte order in serialization.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;iostream&gt;
#include &lt;boost/config.hpp&gt;
int main() {
#if defined(BOOST_LITTLE_ENDIAN)
std::cout &lt;&lt; "System is little-endian.\n";
#elif defined(BOOST_BIG_ENDIAN)
std::cout &lt;&lt; "System is big-endian.\n";
#else
std::cout &lt;&lt; "Unknown endianness.\n";
#endif
return 0;
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_threading_and_synchronization"><a class="anchor" href="#_threading_and_synchronization"></a>Threading and Synchronization</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_DISABLE_THREADS</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Disables multi-threading support in Boost.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_HAS_THREADS</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Indicates if Boost is built with threading support.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_THREAD_USE_LIB</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Forces <a href="https://www.boost.org/libs/thread">Boost.Thread</a> to be used as a static library.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_THREAD_USE_DLL</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Forces <a href="https://www.boost.org/libs/thread">Boost.Thread</a> to be used as a shared library.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_THREAD_PROVIDES_FUTURE</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Enables std::future-like functionality in <a href="https://www.boost.org/libs/thread">Boost.Thread</a>.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_example_3"><a class="anchor" href="#_example_3"></a>Example</h3>
<div class="paragraph">
<p>Using <code>BOOST_HAS_THREADS</code> to ensure threading support is enabled.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;boost/thread.hpp&gt;
#include &lt;iostream&gt;
void threadFunc() {
std::cout &lt;&lt; "Hello from thread!\n";
}
int main() {
#ifdef BOOST_HAS_THREADS
boost::thread myThread(threadFunc);
myThread.join();
#else
std::cout &lt;&lt; "Threads are not supported.\n";
#endif
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_exception_handling"><a class="anchor" href="#_exception_handling"></a>Exception Handling</h2>
<div class="sectionbody">
<table class="tableblock frame-none grid-all stripes-even stretch">
<colgroup>
<col style="width: 33.3333%;">
<col style="width: 66.6667%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top"><strong>Macro</strong></th>
<th class="tableblock halign-left valign-top"><strong>Description</strong></th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_THROW_EXCEPTION</code>(e)</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">A portable way to throw exceptions that integrates with <code>BOOST_NO_EXCEPTIONS</code>.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><code>BOOST_NO_EXCEPTIONS</code></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Disables exception handling.</p></td>
</tr>
</tbody>
</table>
<div class="sect2">
<h3 id="_examples_4"><a class="anchor" href="#_examples_4"></a>Examples</h3>
<div class="paragraph">
<p>Using <code>BOOST_THROW_EXCEPTION</code> to throw exceptions in a portable way.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;boost/exception/exception.hpp&gt;
#include &lt;boost/exception/all.hpp&gt;
#include &lt;iostream&gt;
struct MyException : virtual boost::exception, virtual std::exception {
const char* what() const noexcept override {
return "A Boost exception occurred!";
}
};
void riskyOperation() {
BOOST_THROW_EXCEPTION(MyException());
}
int main() {
try {
riskyOperation();
} catch (const MyException&amp; e) {
std::cout &lt;&lt; "Caught exception: " &lt;&lt; e.what() &lt;&lt; "\n";
}
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>Using <code>BOOST_NO_EXCEPTIONS</code> to ensure compatibility with exception-free environments.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-cpp hljs" data-lang="cpp">#include &lt;iostream&gt;
#include &lt;boost/config.hpp&gt;
void safe_function() {
#ifndef BOOST_NO_EXCEPTIONS
throw std::runtime_error("Something went wrong!");
#else
std::cerr &lt;&lt; "Exceptions are disabled. Handling error manually.\n";
#endif
}
int main() {
try {
safe_function();
} catch (const std::exception&amp; e) {
std::cerr &lt;&lt; "Caught exception: " &lt;&lt; e.what() &lt;&lt; std::endl;
}
}</code></pre>
</div>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also"><a class="anchor" href="#_see_also"></a>See Also</h2>
<div class="sectionbody">
<div class="ulist">
<ul>
<li>
<p><a href="https://www.boost.org/doc/libs/latest/libs/config/doc/html/boost_config/boost_macro_reference.html">Boost Macro Reference</a></p>
</li>
<li>
<p><a href="diagnostics.html" class="xref page">Introduction to Boost Diagnostics</a></p>
</li>
<li>
<p><a href="testing-debugging.html" class="xref page">Testing and Debugging</a></p>
</li>
</ul>
</div>
</div>
</div>
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