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26<div class="titlepage"><div><div><h2 class="title" style="clear: both">
27<a name="boost_integer.minmax"></a><a class="link" href="minmax.html" title="Compile time min/max calculation">Compile time min/max calculation</a>
28</h2></div></div></div>
29<div class="toc"><dl>
30<dt><span class="section"><a href="minmax.html#boost_integer.minmax.synopsis">Synopsis</a></span></dt>
31<dt><span class="section"><a href="minmax.html#boost_integer.minmax.usage">Usage</a></span></dt>
32<dt><span class="section"><a href="minmax.html#boost_integer.minmax.example">Example</a></span></dt>
33<dt><span class="section"><a href="minmax.html#boost_integer.minmax.demonstration_program">Demonstration
34 Program</a></span></dt>
35<dt><span class="section"><a href="minmax.html#boost_integer.minmax.rationale">Rationale</a></span></dt>
36<dt><span class="section"><a href="minmax.html#boost_integer.minmax.credits">Credits</a></span></dt>
37</dl></div>
38<p>
39 The class templates in <a href="../../../../../boost/integer/static_min_max.hpp" target="_top">&lt;boost/integer/static_min_max.hpp&gt;</a>
40 provide a compile-time evaluation of the minimum or maximum of two integers.
41 These facilities are useful for generic programming problems.
42 </p>
43<div class="section">
44<div class="titlepage"><div><div><h3 class="title">
45<a name="boost_integer.minmax.synopsis"></a><a class="link" href="minmax.html#boost_integer.minmax.synopsis" title="Synopsis">Synopsis</a>
46</h3></div></div></div>
47<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
48<span class="special">{</span>
49
50<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined</em></span> <span class="identifier">static_min_max_signed_type</span><span class="special">;</span>
51<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined</em></span> <span class="identifier">static_min_max_unsigned_type</span><span class="special">;</span>
52
53<span class="keyword">template</span> <span class="special">&lt;</span><span class="identifier">static_min_max_signed_type</span> <span class="identifier">Value1</span><span class="special">,</span> <span class="identifier">static_min_max_signed_type</span> <span class="identifier">Value2</span> <span class="special">&gt;</span>
54 <span class="keyword">struct</span> <span class="identifier">static_signed_min</span><span class="special">;</span>
55
56<span class="keyword">template</span> <span class="special">&lt;</span><span class="identifier">static_min_max_signed_type</span> <span class="identifier">Value1</span><span class="special">,</span> <span class="identifier">static_min_max_signed_type</span> <span class="identifier">Value2</span><span class="special">&gt;</span>
57 <span class="keyword">struct</span> <span class="identifier">static_signed_max</span><span class="special">;</span>
58
59<span class="keyword">template</span> <span class="special">&lt;</span><span class="identifier">static_min_max_unsigned_type</span> <span class="identifier">Value1</span><span class="special">,</span> <span class="identifier">static_min_max_unsigned_type</span> <span class="identifier">Value2</span><span class="special">&gt;</span>
60 <span class="keyword">struct</span> <span class="identifier">static_unsigned_min</span><span class="special">;</span>
61
62<span class="keyword">template</span> <span class="special">&lt;</span><span class="identifier">static_min_max_unsigned_type</span> <span class="identifier">Value1</span><span class="special">,</span> <span class="identifier">static_min_max_unsigned_type</span> <span class="identifier">Value2</span><span class="special">&gt;</span>
63 <span class="keyword">struct</span> <span class="identifier">static_unsigned_max</span><span class="special">;</span>
64
65<span class="special">}</span>
66</pre>
67</div>
68<div class="section">
69<div class="titlepage"><div><div><h3 class="title">
70<a name="boost_integer.minmax.usage"></a><a class="link" href="minmax.html#boost_integer.minmax.usage" title="Usage">Usage</a>
71</h3></div></div></div>
72<p>
73 The four class templates provide the combinations for finding the minimum
74 or maximum of two <code class="literal">signed</code> or <code class="literal">unsigned</code>
75 (<code class="literal">long</code>) parameters, <span class="emphasis"><em>Value1</em></span> and <span class="emphasis"><em>Value2</em></span>,
76 at compile-time. Each template has a single static data member, <code class="literal">value</code>,
77 which is set to the respective minimum or maximum of the template's parameters.
78 </p>
79</div>
80<div class="section">
81<div class="titlepage"><div><div><h3 class="title">
82<a name="boost_integer.minmax.example"></a><a class="link" href="minmax.html#boost_integer.minmax.example" title="Example">Example</a>
83</h3></div></div></div>
84<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">integer</span><span class="special">/</span><span class="identifier">static_min_max</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
85
86<span class="keyword">template</span> <span class="special">&lt;</span> <span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="identifier">AddendSize1</span><span class="special">,</span> <span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="identifier">AddendSize2</span> <span class="special">&gt;</span>
87<span class="keyword">class</span> <span class="identifier">adder</span>
88<span class="special">{</span>
89<span class="keyword">public</span><span class="special">:</span>
90 <span class="keyword">static</span> <span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">const</span> <span class="identifier">addend1_size</span> <span class="special">=</span> <span class="identifier">AddendSize1</span><span class="special">;</span>
91 <span class="keyword">static</span> <span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">const</span> <span class="identifier">addend2_size</span> <span class="special">=</span> <span class="identifier">AddendSize2</span><span class="special">;</span>
92 <span class="keyword">static</span> <span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">const</span> <span class="identifier">sum_size</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">static_unsigned_max</span><span class="special">&lt;</span><span class="identifier">AddendSize1</span><span class="special">,</span> <span class="identifier">AddendSize2</span><span class="special">&gt;::</span><span class="identifier">value</span> <span class="special">+</span> <span class="number">1</span><span class="special">;</span>
93
94 <span class="keyword">typedef</span> <span class="keyword">int</span> <span class="identifier">addend1_type</span><span class="special">[</span> <span class="identifier">addend1_size</span> <span class="special">];</span>
95 <span class="keyword">typedef</span> <span class="keyword">int</span> <span class="identifier">addend2_type</span><span class="special">[</span> <span class="identifier">addend2_size</span> <span class="special">];</span>
96 <span class="keyword">typedef</span> <span class="keyword">int</span> <span class="identifier">sum_type</span><span class="special">[</span> <span class="identifier">sum_size</span> <span class="special">];</span>
97
98 <span class="keyword">void</span> <span class="keyword">operator</span> <span class="special">()(</span> <span class="identifier">addend1_type</span> <span class="keyword">const</span> <span class="special">&amp;</span><span class="identifier">a1</span><span class="special">,</span> <span class="identifier">addend2_type</span> <span class="keyword">const</span> <span class="special">&amp;</span><span class="identifier">a2</span><span class="special">,</span> <span class="identifier">sum_type</span> <span class="special">&amp;</span><span class="identifier">s</span> <span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
99<span class="special">};</span>
100
101<span class="comment">//...</span>
102
103<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
104<span class="special">{</span>
105 <span class="keyword">int</span> <span class="keyword">const</span> <span class="identifier">a1</span><span class="special">[]</span> <span class="special">=</span> <span class="special">{</span> <span class="number">0</span><span class="special">,</span> <span class="number">4</span><span class="special">,</span> <span class="number">3</span> <span class="special">};</span> <span class="comment">// 340</span>
106 <span class="keyword">int</span> <span class="keyword">const</span> <span class="identifier">a2</span><span class="special">[]</span> <span class="special">=</span> <span class="special">{</span> <span class="number">9</span><span class="special">,</span> <span class="number">8</span> <span class="special">};</span> <span class="comment">// 89</span>
107 <span class="keyword">int</span> <span class="identifier">s</span><span class="special">[</span> <span class="number">4</span> <span class="special">];</span>
108 <span class="identifier">adder</span><span class="special">&lt;</span><span class="number">3</span><span class="special">,</span><span class="number">2</span><span class="special">&gt;</span> <span class="identifier">obj</span><span class="special">;</span>
109
110 <span class="identifier">obj</span><span class="special">(</span> <span class="identifier">a1</span><span class="special">,</span> <span class="identifier">a2</span><span class="special">,</span> <span class="identifier">s</span> <span class="special">);</span> <span class="comment">// 's' should be 429 or { 9, 2, 4, 0 }</span>
111 <span class="comment">//...</span>
112<span class="special">}</span>
113</pre>
114</div>
115<div class="section">
116<div class="titlepage"><div><div><h3 class="title">
117<a name="boost_integer.minmax.demonstration_program"></a><a class="link" href="minmax.html#boost_integer.minmax.demonstration_program" title="Demonstration Program">Demonstration
118 Program</a>
119</h3></div></div></div>
120<p>
121 The program <a href="../../../test/static_min_max_test.cpp" target="_top">static_min_max_test.cpp</a>
122 is a simplistic demonstration of various comparisons using the compile-time
123 extrema class templates.
124 </p>
125</div>
126<div class="section">
127<div class="titlepage"><div><div><h3 class="title">
128<a name="boost_integer.minmax.rationale"></a><a class="link" href="minmax.html#boost_integer.minmax.rationale" title="Rationale">Rationale</a>
129</h3></div></div></div>
130<p>
131 Sometimes the minimum or maximum of several values needs to be found for
132 later compile-time processing, <span class="emphasis"><em>e.g.</em></span> for a bound for
133 another class template.
134 </p>
135</div>
136<div class="section">
137<div class="titlepage"><div><div><h3 class="title">
138<a name="boost_integer.minmax.credits"></a><a class="link" href="minmax.html#boost_integer.minmax.credits" title="Credits">Credits</a>
139</h3></div></div></div>
140<p>
141 The author of the Boost compile-time extrema class templates is <a href="http://www.boost.org/people/daryle_walker.html" target="_top">Daryle
142 Walker</a>.
143 </p>
144</div>
145</div>
146<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
147<td align="left"></td>
148<td align="right"><div class="copyright-footer">Copyright &#169; 2001-2009 Beman
149 Dawes, Daryle Walker, Gennaro Prota, John Maddock<p>
150 Distributed under the Boost Software License, Version 1.0. (See accompanying
151 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
152 </p>
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