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Eric Niebler 5b6d08974e Merged revisions 40861-40888 via svnmerge from 
https://svn.boost.org/svn/boost/trunk

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  r40862 | dave | 2007-11-06 15:39:09 -0800 (Tue, 06 Nov 2007) | 2 lines
  
  Added missing copyright/license
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  r40863 | djowel | 2007-11-06 18:12:28 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40864 | aaron_windsor | 2007-11-06 18:30:38 -0800 (Tue, 06 Nov 2007) | 1 line
  
  Shortening file name of a graph test to < 32 characters
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  r40865 | djowel | 2007-11-06 18:34:18 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40866 | djowel | 2007-11-06 19:06:23 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40867 | djowel | 2007-11-06 19:23:31 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40868 | djowel | 2007-11-06 19:25:59 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40869 | djowel | 2007-11-06 19:27:38 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40870 | djowel | 2007-11-06 19:30:01 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40871 | djowel | 2007-11-06 19:35:49 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40872 | djowel | 2007-11-06 19:37:51 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40873 | djowel | 2007-11-06 19:46:23 -0800 (Tue, 06 Nov 2007) | 1 line
  
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  r40874 | chris_kohlhoff | 2007-11-06 22:49:36 -0800 (Tue, 06 Nov 2007) | 2 lines
  
  Add copyright notice.
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  r40875 | chris_kohlhoff | 2007-11-06 22:53:17 -0800 (Tue, 06 Nov 2007) | 2 lines
  
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  r40876 | chris_kohlhoff | 2007-11-06 23:23:53 -0800 (Tue, 06 Nov 2007) | 2 lines
  
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  r40877 | joaquin | 2007-11-07 00:45:27 -0800 (Wed, 07 Nov 2007) | 1 line
  
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  r40878 | johnmaddock | 2007-11-07 02:07:08 -0800 (Wed, 07 Nov 2007) | 1 line
  
  Ooops, got the pp-logic wrong and disable long double support for all Unix platforms, instead of just Intel on Linux prior to version 10.
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  r40879 | johnmaddock | 2007-11-07 02:09:50 -0800 (Wed, 07 Nov 2007) | 1 line
  
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  r40880 | t_schwinger | 2007-11-07 02:14:42 -0800 (Wed, 07 Nov 2007) | 3 lines
  
  adds FunctionTypes
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  r40881 | johnmaddock | 2007-11-07 03:50:02 -0800 (Wed, 07 Nov 2007) | 1 line
  
  Change test (again) so that the range of values tested matches original test: last change started testing more extreme input values, which caused regressions on Mac OS X.
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  r40882 | johnmaddock | 2007-11-07 03:59:39 -0800 (Wed, 07 Nov 2007) | 3 lines
  
  Disabled use of long double when BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS is defined.
  Disabled special-double precision error rates when BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS is defined.
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  r40883 | johnmaddock | 2007-11-07 04:04:01 -0800 (Wed, 07 Nov 2007) | 1 line
  
  Oops get the name of test right!
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  r40884 | anthonyw | 2007-11-07 04:10:17 -0800 (Wed, 07 Nov 2007) | 1 line
  
  Added missing licence and copyright
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  r40885 | garcia | 2007-11-07 04:25:16 -0800 (Wed, 07 Nov 2007) | 2 lines
  
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  r40886 | garcia | 2007-11-07 05:38:53 -0800 (Wed, 07 Nov 2007) | 2 lines
  
  Exception was accepted.
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  r40887 | fcacciola | 2007-11-07 06:12:15 -0800 (Wed, 07 Nov 2007) | 1 line
  
  Added explicit failures for newly discovered GCC const ref binding bug (see Ticket #1301)
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[SVN r40891]
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<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>fold</title>
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<div class="section" lang="en">
<div class="titlepage"><div><div><h5 class="title">
<a name="fusion.algorithm.iteration.functions.fold"></a><a href="fold.html" title="fold">fold</a></h5></div></div></div>
<a name="fusion.algorithm.iteration.functions.fold.description"></a><h6>
<a name="id575528"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.description">Description</a>
</h6>
<p>
For a sequence <tt class="computeroutput"><span class="identifier">Seq</span></tt>, initial
state, and binary function object or function pointer <tt class="computeroutput"><span class="identifier">f</span></tt>,
fold repeatedly applies binary <tt class="computeroutput"><span class="identifier">f</span></tt>
to each element of <tt class="computeroutput"><span class="identifier">Seq</span></tt>
and the previous state.
</p>
<a name="fusion.algorithm.iteration.functions.fold.synopsis"></a><h6>
<a name="id575608"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.synopsis">Synopsis</a>
</h6>
<pre class="programlisting">
<span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <span class="identifier">Sequence</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">State</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">F</span>
<span class="special">&gt;</span>
<span class="keyword">typename</span> <a href="../metafunctions/fold.html" title="fold"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">fold</span></tt></a><span class="special">&lt;</span><span class="identifier">Sequence</span><span class="special">,</span> <span class="identifier">State</span><span class="special">,</span> <span class="identifier">F</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">fold</span><span class="special">(</span>
<span class="identifier">Sequence</span><span class="special">&amp;</span> <span class="identifier">seq</span><span class="special">,</span> <span class="identifier">State</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">initial_state</span><span class="special">,</span> <span class="identifier">F</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">f</span><span class="special">);</span>
</pre>
<div class="table">
<a name="id575867"></a><p class="title"><b>Table 1.33. Parameters</b></p>
<table class="table" summary="Parameters">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
Parameter
</p>
</th>
<th>
<p>
Requirement
</p>
</th>
<th>
<p>
Description
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<tt class="computeroutput"><span class="identifier">seq</span></tt>
</p>
</td>
<td>
<p>
A model of <a href="../../../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a>,<tt class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">e</span><span class="special">,</span><span class="identifier">s</span><span class="special">)</span></tt> must be a valid expression for
each element <tt class="computeroutput"><span class="identifier">e</span></tt>
in <tt class="computeroutput"><span class="identifier">seq</span></tt>, and current
state <tt class="computeroutput"><span class="identifier">s</span></tt>
</p>
</td>
<td>
<p>
Operation's argument
</p>
</td>
</tr>
<tr>
<td>
<p>
<tt class="computeroutput"><span class="identifier">initial_state</span></tt>
</p>
</td>
<td>
<p>
Any type
</p>
</td>
<td>
<p>
Initial state
</p>
</td>
</tr>
<tr>
<td>
<p>
<tt class="computeroutput"><span class="identifier">f</span></tt>
</p>
</td>
<td>
<p>
<tt class="computeroutput"><a href="http://www.boost.org/libs/utility/utility.htm#result_of" target="_top"><tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">result_of</span></tt></a><span class="special">&lt;</span><span class="identifier">F</span><span class="special">(</span><span class="identifier">E</span><span class="special">,</span><span class="identifier">S</span><span class="special">)&gt;::</span><span class="identifier">type</span></tt> is the return type of <tt class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">e</span><span class="special">,</span><span class="identifier">s</span><span class="special">)</span></tt>
for each element <tt class="computeroutput"><span class="identifier">e</span></tt>
of type <tt class="computeroutput"><span class="identifier">E</span></tt> in <tt class="computeroutput"><span class="identifier">seq</span></tt>, and current state <tt class="computeroutput"><span class="identifier">s</span></tt> of type <tt class="computeroutput"><span class="identifier">S</span></tt>
</p>
</td>
<td>
<p>
Operation's argument
</p>
</td>
</tr>
</tbody>
</table>
</div>
<a name="fusion.algorithm.iteration.functions.fold.expression_semantics"></a><h6>
<a name="id576277"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.expression_semantics">Expression
Semantics</a>
</h6>
<pre class="programlisting">
<span class="identifier">fold</span><span class="special">(</span><span class="identifier">seq</span><span class="special">,</span> <span class="identifier">initial_state</span><span class="special">,</span> <span class="identifier">f</span><span class="special">);</span>
</pre>
<p>
<span class="bold"><b>Return type</b></span>: Any type
</p>
<p>
<span class="bold"><b>Semantics</b></span>: Equivalent to <tt class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">eN</span> <span class="special">....</span><span class="identifier">f</span><span class="special">(</span><span class="identifier">e2</span><span class="special">,</span><span class="identifier">f</span><span class="special">(</span><span class="identifier">e1</span><span class="special">,</span><span class="identifier">initial_state</span><span class="special">)))</span></tt>
where <tt class="computeroutput"><span class="identifier">e1</span> <span class="special">...</span><span class="identifier">eN</span></tt> are the elements of <tt class="computeroutput"><span class="identifier">seq</span></tt>.
</p>
<a name="fusion.algorithm.iteration.functions.fold.complexity"></a><h6>
<a name="id576487"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.complexity">Complexity</a>
</h6>
<p>
Linear, exactly <tt class="computeroutput"><a href="../../../sequence/intrinsic/metafunctions/size.html" title="size"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">size</span></tt></a><span class="special">&lt;</span><span class="identifier">Sequence</span><span class="special">&gt;::</span><span class="identifier">value</span></tt> applications of <tt class="computeroutput"><span class="identifier">f</span></tt>.
</p>
<a name="fusion.algorithm.iteration.functions.fold.header"></a><h6>
<a name="id576582"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.header">Header</a>
</h6>
<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">fusion</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">/</span><span class="identifier">iteration</span><span class="special">/</span><span class="identifier">fold</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">fold</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<a name="fusion.algorithm.iteration.functions.fold.example"></a><h6>
<a name="id576752"></a>
<a href="fold.html#fusion.algorithm.iteration.functions.fold.example">Example</a>
</h6>
<pre class="programlisting">
<span class="keyword">struct</span> <span class="identifier">make_string</span>
<span class="special">{</span>
<span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">result_type</span><span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="keyword">operator</span><span class="special">()(</span><span class="keyword">const</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">t</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&amp;</span> <span class="identifier">str</span><span class="special">)</span> <span class="keyword">const</span>
<span class="special">{</span>
<span class="keyword">return</span> <span class="identifier">str</span> <span class="special">+</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">lexical_cast</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;(</span><span class="identifier">t</span><span class="special">);</span>
<span class="special">}</span>
<span class="special">};</span>
<span class="special">...</span>
<span class="keyword">const</span> <a href="../../../container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">vec</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">);</span>
<span class="identifier">assert</span><span class="special">(</span><a href="fold.html" title="fold"><tt class="computeroutput"><span class="identifier">fold</span></tt></a><span class="special">(</span><span class="identifier">vec</span><span class="special">,</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">(</span><span class="string">""</span><span class="special">),</span> <span class="identifier">make_string</span><span class="special">())</span> <span class="special">==</span> <span class="string">"12"</span><span class="special">);</span>
</pre>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer"><small>Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias
Schwinger<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
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>)
</p></small></div></td>
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