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<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Notes</title>
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</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="fusion.notes"></a><a class="link" href="notes.html" title="Notes">Notes</a>
</h2></div></div></div>
<a name="fusion.notes.recursive_inlined_functions"></a><h4>
<a name="id2839870"></a>
<a class="link" href="notes.html#fusion.notes.recursive_inlined_functions">Recursive Inlined
<a name="fusion.notes"></a><a href="notes.html" title="Notes">Notes</a></h2></div></div></div>
<a name="fusion.notes.recursive_inlined_functions"></a><h3>
<a name="id685001"></a>
<a href="notes.html#fusion.notes.recursive_inlined_functions">Recursive Inlined
Functions</a>
</h4>
</h3>
<p>
An interesting peculiarity of functions like <a class="link" href="sequence/intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></a> when applied to a <a class="link" href="sequence/concepts/forward_sequence.html" title="Forward Sequence">Forward
Sequence</a> like <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a>
An interesting peculiarity of functions like <a href="sequence/intrinsic/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a> when applied to a <a href="sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a> like <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a>
is that what could have been linear runtime complexity effectively becomes
constant O(1) due to compiler optimization of C++ inlined functions, however
deeply recursive (up to a certain compiler limit of course). Compile time complexity
remains linear.
</p>
<a name="fusion.notes.overloaded_functions"></a><h4>
<a name="id2839940"></a>
<a class="link" href="notes.html#fusion.notes.overloaded_functions">Overloaded Functions</a>
</h4>
<a name="fusion.notes.overloaded_functions"></a><h3>
<a name="id685076"></a>
<a href="notes.html#fusion.notes.overloaded_functions">Overloaded Functions</a>
</h3>
<p>
Associative sequences use function overloading to implement membership testing
and type associated key lookup. This amounts to constant runtime and amortized
constant compile time complexities. There is an overloaded function, <code class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">k</span><span class="special">)</span></code>, for each key <span class="emphasis"><em>type</em></span> <code class="computeroutput"><span class="identifier">k</span></code>. The compiler chooses the appropriate function
given a key, <code class="computeroutput"><span class="identifier">k</span></code>.
constant compile time complexities. There is an overloaded function, <tt class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">k</span><span class="special">)</span></tt>, for each key <span class="emphasis"><em>type</em></span> <tt class="computeroutput"><span class="identifier">k</span></tt>. The compiler chooses the appropriate function
given a key, <tt class="computeroutput"><span class="identifier">k</span></tt>.
</p>
<a name="fusion.notes.tag_dispatching"></a><h4>
<a name="id2840015"></a>
<a class="link" href="notes.html#fusion.notes.tag_dispatching">Tag Dispatching</a>
</h4>
<a name="fusion.notes.tag_dispatching"></a><h3>
<a name="id685159"></a>
<a href="notes.html#fusion.notes.tag_dispatching">Tag Dispatching</a>
</h3>
<p>
Tag dispatching is a generic programming technique for selecting template specializations.
There are typically 3 components involved in the tag dispatching mechanism:
@ -69,7 +70,7 @@
</li>
</ol></div>
<p>
For example, the fusion <code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></code> metafunction
For example, the fusion <tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></tt> metafunction
is implemented as follows:
</p>
<pre class="programlisting">
@ -87,24 +88,24 @@
</p>
<div class="orderedlist"><ol type="1">
<li>
<code class="computeroutput"><span class="identifier">Sequence</span></code> is the type for
which a suitable implementation of <code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin_impl</span></code>
<tt class="computeroutput"><span class="identifier">Sequence</span></tt> is the type for
which a suitable implementation of <tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin_impl</span></tt>
is required
</li>
<li>
<code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">tag_of</span></code> is the metafunction that associates
<code class="computeroutput"><span class="identifier">Sequence</span></code> with an appropriate
<tt class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">tag_of</span></tt> is the metafunction that associates
<tt class="computeroutput"><span class="identifier">Sequence</span></tt> with an appropriate
tag
</li>
<li>
<code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin_impl</span></code> is the template which is specialized
<tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin_impl</span></tt> is the template which is specialized
to provide an implementation for each tag type
</li>
</ol></div>
<a name="fusion.notes.extensibility"></a><h4>
<a name="id2840362"></a>
<a class="link" href="notes.html#fusion.notes.extensibility">Extensibility</a>
</h4>
<a name="fusion.notes.extensibility"></a><h3>
<a name="id685543"></a>
<a href="notes.html#fusion.notes.extensibility">Extensibility</a>
</h3>
<p>
Unlike <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, there
is no extensibe sequence concept in fusion. This does not mean that Fusion
@ -112,69 +113,69 @@
extensible. It is just that the manner of sequence extension in Fusion is diferent
from both <a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>
and <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a> on account
of the lazy nature of fusion <a class="link" href="algorithm.html" title="Algorithm">Algorithms</a>.
of the lazy nature of fusion <a href="algorithm.html" title="Algorithm">Algorithms</a>.
<a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>
containers extend themselves in place though member functions such as <a class="link" href="algorithm/transformation/functions/push_back.html" title="push_back"><code class="computeroutput"><span class="identifier">push_back</span></code></a> and <a class="link" href="algorithm/transformation/functions/insert.html" title="insert"><code class="computeroutput"><span class="identifier">insert</span></code></a>. <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>
containers extend themselves in place though member functions such as <a href="algorithm/transformation/functions/push_back.html" title="push_back"><tt class="computeroutput"><span class="identifier">push_back</span></tt></a> and <a href="algorithm/transformation/functions/insert.html" title="insert"><tt class="computeroutput"><span class="identifier">insert</span></tt></a>. <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>
sequences, on the other hand, are extended through "intrinsic" functions
that actually return whole sequences. <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>
is purely functional and can not have side effects. For example, <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>'s
<code class="computeroutput"><span class="identifier">push_back</span></code> does not actually
mutate an <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">vector</span></code>. It can't do that. Instead, it returns
an extended <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">vector</span></code>.
<tt class="computeroutput"><span class="identifier">push_back</span></tt> does not actually
mutate an <tt class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">vector</span></tt>. It can't do that. Instead, it returns
an extended <tt class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">vector</span></tt>.
</p>
<p>
Like <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, Fusion
too is purely functional and can not have side effects. With runtime efficiency
in mind, Fusion sequences are extended through generic functions that return
<a class="link" href="view.html" title="View">Views</a>. <a class="link" href="view.html" title="View">Views</a>
<a href="view.html" title="View">Views</a>. <a href="view.html" title="View">Views</a>
are sequences that do not actually contain data, but instead impart an alternative
presentation over the data from one or more underlying sequences. <a class="link" href="view.html" title="View">Views</a>
presentation over the data from one or more underlying sequences. <a href="view.html" title="View">Views</a>
are proxies. They provide an efficient yet purely functional way to work on
potentially expensive sequence operations. For example, given a <a class="link" href="container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a>, Fusion's <a class="link" href="algorithm/transformation/functions/push_back.html" title="push_back"><code class="computeroutput"><span class="identifier">push_back</span></code></a> returns a <a class="link" href="view/joint_view.html" title="joint_view"><code class="computeroutput"><span class="identifier">joint_view</span></code></a>, instead of an actual extended
<a class="link" href="container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a>.
A <a class="link" href="view/joint_view.html" title="joint_view"><code class="computeroutput"><span class="identifier">joint_view</span></code></a>
potentially expensive sequence operations. For example, given a <a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a>, Fusion's <a href="algorithm/transformation/functions/push_back.html" title="push_back"><tt class="computeroutput"><span class="identifier">push_back</span></tt></a> returns a <a href="view/joint_view.html" title="joint_view"><tt class="computeroutput"><span class="identifier">joint_view</span></tt></a>, instead of an actual extended
<a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a>.
A <a href="view/joint_view.html" title="joint_view"><tt class="computeroutput"><span class="identifier">joint_view</span></tt></a>
holds a reference to the original sequence plus the appended data --making
it very cheap to pass around.
</p>
<a name="fusion.notes.element_conversion"></a><h4>
<a name="id2840650"></a>
<a class="link" href="notes.html#fusion.notes.element_conversion">Element Conversion</a>
</h4>
<a name="fusion.notes.element_conversion"></a><h3>
<a name="id685862"></a>
<a href="notes.html#fusion.notes.element_conversion">Element Conversion</a>
</h3>
<p>
Functions that take in elemental values to form sequences (e.g. <a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a>) convert their arguments
Functions that take in elemental values to form sequences (e.g. <a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a>) convert their arguments
to something suitable to be stored as a sequence element. In general, the element
types are stored as plain values. Example:
</p>
<pre class="programlisting">
<a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="char">'x'</span><span class="special">)</span>
<a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="char">'x'</span><span class="special">)</span>
</pre>
<p>
returns a <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><code class="computeroutput"><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span>
<span class="keyword">char</span><span class="special">&gt;</span></code>.
returns a <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a><tt class="computeroutput"><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span>
<span class="keyword">char</span><span class="special">&gt;</span></tt>.
</p>
<p>
There are a few exceptions, however.
</p>
<p>
<span class="bold"><strong>Arrays:</strong></span>
<span class="bold"><b>Arrays:</b></span>
</p>
<p>
Array arguments are deduced to reference to const types. For example
<sup>[<a name="id2840795" href="#ftn.id2840795" class="footnote">14</a>]</sup>
<sup>[<a name="id686021" href="#ftn.id686021">14</a>]</sup>
:
</p>
<pre class="programlisting">
<a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="string">"Donald"</span><span class="special">,</span> <span class="string">"Daisy"</span><span class="special">)</span>
<a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="string">"Donald"</span><span class="special">,</span> <span class="string">"Daisy"</span><span class="special">)</span>
</pre>
<p>
creates a <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a>
creates a <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a>
of type
</p>
<pre class="programlisting">
<a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">char</span> <span class="special">(&amp;)[</span><span class="number">7</span><span class="special">],</span> <span class="keyword">const</span> <span class="keyword">char</span> <span class="special">(&amp;)[</span><span class="number">6</span><span class="special">]&gt;</span>
<a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">char</span> <span class="special">(&amp;)[</span><span class="number">7</span><span class="special">],</span> <span class="keyword">const</span> <span class="keyword">char</span> <span class="special">(&amp;)[</span><span class="number">6</span><span class="special">]&gt;</span>
</pre>
<p>
<span class="bold"><strong>Function pointers:</strong></span>
<span class="bold"><b>Function pointers:</b></span>
</p>
<p>
Function pointers are deduced to the plain non-reference type (i.e. to plain
@ -183,38 +184,38 @@
<pre class="programlisting">
<span class="keyword">void</span> <span class="identifier">f</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span><span class="special">);</span>
<span class="special">...</span>
<a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(&amp;</span><span class="identifier">f</span><span class="special">);</span>
<a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(&amp;</span><span class="identifier">f</span><span class="special">);</span>
</pre>
<p>
creates a <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a>
creates a <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a>
of type
</p>
<pre class="programlisting">
<a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><span class="special">&lt;</span><span class="keyword">void</span> <span class="special">(*)(</span><span class="keyword">int</span><span class="special">)&gt;</span>
<a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a><span class="special">&lt;</span><span class="keyword">void</span> <span class="special">(*)(</span><span class="keyword">int</span><span class="special">)&gt;</span>
</pre>
<a name="fusion.notes.boost__ref"></a><h4>
<a name="id2841191"></a>
<a class="link" href="notes.html#fusion.notes.boost__ref">boost::ref</a>
</h4>
<a name="fusion.notes.boost__ref"></a><h3>
<a name="id686456"></a>
<a href="notes.html#fusion.notes.boost__ref">boost::ref</a>
</h3>
<p>
Fusion's generation functions (e.g. <a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a>) by default stores the element
Fusion's generation functions (e.g. <a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a>) by default stores the element
types as plain non-reference types. Example:
</p>
<pre class="programlisting">
<span class="keyword">void</span> <span class="identifier">foo</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">A</span><span class="special">&amp;</span> <span class="identifier">a</span><span class="special">,</span> <span class="identifier">B</span><span class="special">&amp;</span> <span class="identifier">b</span><span class="special">)</span> <span class="special">{</span>
<span class="special">...</span>
<a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">a</span><span class="special">,</span> <span class="identifier">b</span><span class="special">)</span>
<a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">a</span><span class="special">,</span> <span class="identifier">b</span><span class="special">)</span>
</pre>
<p>
creates a <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a>
creates a <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a>
of type
</p>
<pre class="programlisting">
<a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span> <span class="identifier">B</span><span class="special">&gt;</span>
<a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span> <span class="identifier">B</span><span class="special">&gt;</span>
</pre>
<p>
Sometimes the plain non-reference type is not desired. You can use <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span></code>
and <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">cref</span></code> to store references or const references
Sometimes the plain non-reference type is not desired. You can use <tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span></tt>
and <tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">cref</span></tt> to store references or const references
(respectively) instead. The mechanism does not compromise const correctness
since a const object wrapped with ref results in a tuple element with const
reference type (see the fifth code line below). Examples:
@ -224,11 +225,11 @@
</p>
<pre class="programlisting">
<span class="identifier">A</span> <span class="identifier">a</span><span class="special">;</span> <span class="identifier">B</span> <span class="identifier">b</span><span class="special">;</span> <span class="keyword">const</span> <span class="identifier">A</span> <span class="identifier">ca</span> <span class="special">=</span> <span class="identifier">a</span><span class="special">;</span>
<a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">cref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">b</span><span class="special">);</span> <span class="comment">// creates list&lt;const A&amp;, B&gt;
</span><a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">b</span><span class="special">);</span> <span class="comment">// creates list&lt;A&amp;, B&gt;
</span><a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">cref</span><span class="special">(</span><span class="identifier">b</span><span class="special">));</span> <span class="comment">// creates list&lt;A&amp;, const B&amp;&gt;
</span><a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">cref</span><span class="special">(</span><span class="identifier">ca</span><span class="special">));</span> <span class="comment">// creates list&lt;const A&amp;&gt;
</span><a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">ca</span><span class="special">));</span> <span class="comment">// creates list&lt;const A&amp;&gt;
<a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">cref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">b</span><span class="special">);</span> <span class="comment">// creates list&lt;const A&amp;, B&gt;
</span><a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">b</span><span class="special">);</span> <span class="comment">// creates list&lt;A&amp;, B&gt;
</span><a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a</span><span class="special">),</span> <span class="identifier">cref</span><span class="special">(</span><span class="identifier">b</span><span class="special">));</span> <span class="comment">// creates list&lt;A&amp;, const B&amp;&gt;
</span><a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">cref</span><span class="special">(</span><span class="identifier">ca</span><span class="special">));</span> <span class="comment">// creates list&lt;const A&amp;&gt;
</span><a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a><span class="special">(</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">ca</span><span class="special">));</span> <span class="comment">// creates list&lt;const A&amp;&gt;
</span></pre>
<p>
See <a href="http://www.boost.org/doc/html/ref.html" target="_top">Boost.Ref</a> for
@ -236,11 +237,11 @@
</p>
<div class="footnotes">
<br><hr width="100" align="left">
<div class="footnote"><p><sup>[<a name="ftn.id2840795" href="#id2840795" class="para">14</a>] </sup>
<div class="footnote"><p><sup>[<a name="ftn.id686021" href="#id686021">14</a>] </sup>
Note that the type of a string literal is an array of const characters,
not <code class="computeroutput"><span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span></code>. To get <a class="link" href="container/generation/functions/make_list.html" title="make_list"><code class="computeroutput"><span class="identifier">make_list</span></code></a> to create a <a class="link" href="container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a> with an element of a non-const
array type one must use the <code class="computeroutput"><span class="identifier">ref</span></code>
wrapper (see <a class="link" href="notes.html#fusion.notes.boost__ref"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span></code></a>).
not <tt class="computeroutput"><span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span></tt>. To get <a href="container/generation/functions/make_list.html" title="make_list"><tt class="computeroutput"><span class="identifier">make_list</span></tt></a> to create a <a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a> with an element of a non-const
array type one must use the <tt class="computeroutput"><span class="identifier">ref</span></tt>
wrapper (see <a href="notes.html#fusion.notes.boost__ref"><tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span></tt></a>).
</p></div>
</div>
</div>