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25 | <div class="section"> | |
26 | <div class="titlepage"><div><div><h4 class="title"> | |
27 | <a name="fiber.when_any.when_all_functionality.when_all__return_values"></a><a class="link" href="when_all__return_values.html" title="when_all, return values">when_all, | |
28 | return values</a> | |
29 | </h4></div></div></div> | |
30 | <p> | |
31 | As soon as we want to collect return values from all the task functions, | |
32 | we can see right away how to reuse <a class="link" href="../when_any/when_any__return_value.html#wait_first_value"><code class="computeroutput"><span class="identifier">wait_first_value</span><span class="special">()</span></code></a>'s | |
33 | channel<T> for the purpose. All we have to do is avoid closing it | |
34 | after the first value! | |
35 | </p> | |
36 | <p> | |
37 | But in fact, collecting multiple values raises an interesting question: | |
38 | do we <span class="emphasis"><em>really</em></span> want to wait until the slowest of them | |
39 | has arrived? Wouldn't we rather process each result as soon as it becomes | |
40 | available? | |
41 | </p> | |
42 | <p> | |
43 | Fortunately we can present both APIs. Let's define <code class="computeroutput"><span class="identifier">wait_all_values_source</span><span class="special">()</span></code> to return <code class="computeroutput"><span class="identifier">shared_ptr</span><span class="special"><</span><span class="identifier">unbounded_channel</span><span class="special"><</span><span class="identifier">T</span><span class="special">>></span></code>.<sup>[<a name="fiber.when_any.when_all_functionality.when_all__return_values.f0" href="#ftn.fiber.when_any.when_all_functionality.when_all__return_values.f0" class="footnote">6</a>]</sup> | |
44 | </p> | |
45 | <p> | |
46 | <a name="wait_all_values"></a>Given <code class="computeroutput"><span class="identifier">wait_all_values_source</span><span class="special">()</span></code>, it's straightforward to implement <code class="computeroutput"><span class="identifier">wait_all_values</span><span class="special">()</span></code>: | |
47 | </p> | |
48 | <p> | |
49 | </p> | |
50 | <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">Fn</span><span class="special">,</span> <span class="keyword">typename</span> <span class="special">...</span> <span class="identifier">Fns</span> <span class="special">></span> | |
51 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">result_of</span><span class="special"><</span> <span class="identifier">Fn</span><span class="special">()</span> <span class="special">>::</span><span class="identifier">type</span> <span class="special">></span> | |
52 | <span class="identifier">wait_all_values</span><span class="special">(</span> <span class="identifier">Fn</span> <span class="special">&&</span> <span class="identifier">function</span><span class="special">,</span> <span class="identifier">Fns</span> <span class="special">&&</span> <span class="special">...</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">{</span> | |
53 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">count</span><span class="special">(</span> <span class="number">1</span> <span class="special">+</span> <span class="keyword">sizeof</span> <span class="special">...</span> <span class="special">(</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">);</span> | |
54 | <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">result_of</span><span class="special"><</span> <span class="identifier">Fn</span><span class="special">()</span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">return_t</span><span class="special">;</span> | |
55 | <span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span> <span class="identifier">return_t</span> <span class="special">></span> <span class="identifier">vector_t</span><span class="special">;</span> | |
56 | <span class="identifier">vector_t</span> <span class="identifier">results</span><span class="special">;</span> | |
57 | <span class="identifier">results</span><span class="special">.</span><span class="identifier">reserve</span><span class="special">(</span> <span class="identifier">count</span><span class="special">);</span> | |
58 | ||
59 | <span class="comment">// get channel</span> | |
60 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</span><span class="special"><</span> <span class="identifier">return_t</span> <span class="special">></span> <span class="special">></span> <span class="identifier">channel</span> <span class="special">=</span> | |
61 | <span class="identifier">wait_all_values_source</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span> <span class="identifier">Fn</span> <span class="special">>(</span> <span class="identifier">function</span><span class="special">),</span> | |
62 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span> <span class="identifier">Fns</span> <span class="special">>(</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">...</span> <span class="special">);</span> | |
63 | <span class="comment">// fill results vector</span> | |
64 | <span class="identifier">return_t</span> <span class="identifier">value</span><span class="special">;</span> | |
65 | <span class="keyword">while</span> <span class="special">(</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">channel_op_status</span><span class="special">::</span><span class="identifier">success</span> <span class="special">==</span> <span class="identifier">channel</span><span class="special">-></span><span class="identifier">pop</span><span class="special">(</span><span class="identifier">value</span><span class="special">)</span> <span class="special">)</span> <span class="special">{</span> | |
66 | <span class="identifier">results</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">value</span><span class="special">);</span> | |
67 | <span class="special">}</span> | |
68 | <span class="comment">// return vector to caller</span> | |
69 | <span class="keyword">return</span> <span class="identifier">results</span><span class="special">;</span> | |
70 | <span class="special">}</span> | |
71 | </pre> | |
72 | <p> | |
73 | </p> | |
74 | <p> | |
75 | It might be called like this: | |
76 | </p> | |
77 | <p> | |
78 | </p> | |
79 | <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</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="identifier">values</span> <span class="special">=</span> | |
80 | <span class="identifier">wait_all_values</span><span class="special">(</span> | |
81 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wav_late"</span><span class="special">,</span> <span class="number">150</span><span class="special">);</span> <span class="special">},</span> | |
82 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wav_middle"</span><span class="special">,</span> <span class="number">100</span><span class="special">);</span> <span class="special">},</span> | |
83 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wav_early"</span><span class="special">,</span> <span class="number">50</span><span class="special">);</span> <span class="special">});</span> | |
84 | </pre> | |
85 | <p> | |
86 | </p> | |
87 | <p> | |
88 | As you can see from the loop in <code class="computeroutput"><span class="identifier">wait_all_values</span><span class="special">()</span></code>, instead of requiring its caller to count | |
89 | values, we define <code class="computeroutput"><span class="identifier">wait_all_values_source</span><span class="special">()</span></code> to <a class="link" href="../../synchronization/channels.html#unbounded_channel_close"><code class="computeroutput">unbounded_channel::close()</code></a> the | |
90 | channel when done. But how do we do that? Each producer fiber is independent. | |
91 | It has no idea whether it is the last one to <a class="link" href="../../synchronization/channels.html#unbounded_channel_push"><code class="computeroutput">unbounded_channel::push()</code></a> a | |
92 | value. | |
93 | </p> | |
94 | <p> | |
95 | <a name="wait_nchannel"></a>We can address that problem with a counting | |
96 | façade for the <code class="computeroutput"><span class="identifier">unbounded_channel</span><span class="special"><></span></code>. In fact, our façade need only | |
97 | support the producer end of the channel. | |
98 | </p> | |
99 | <p> | |
100 | </p> | |
101 | <pre class="programlisting"><span class="comment">// Introduce a channel facade that closes the channel once a specific number</span> | |
102 | <span class="comment">// of items has been pushed. This allows an arbitrary consumer to read until</span> | |
103 | <span class="comment">// 'closed' without itself having to count items.</span> | |
104 | <span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">T</span> <span class="special">></span> | |
105 | <span class="keyword">class</span> <span class="identifier">nchannel</span> <span class="special">{</span> | |
106 | <span class="keyword">public</span><span class="special">:</span> | |
107 | <span class="identifier">nchannel</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span> <span class="special">></span> <span class="identifier">cp</span><span class="special">,</span> | |
108 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">lm</span><span class="special">):</span> | |
109 | <span class="identifier">channel_</span><span class="special">(</span> <span class="identifier">cp</span><span class="special">),</span> | |
110 | <span class="identifier">limit_</span><span class="special">(</span> <span class="identifier">lm</span><span class="special">)</span> <span class="special">{</span> | |
111 | <span class="identifier">assert</span><span class="special">(</span><span class="identifier">channel_</span><span class="special">);</span> | |
112 | <span class="keyword">if</span> <span class="special">(</span> <span class="number">0</span> <span class="special">==</span> <span class="identifier">limit_</span><span class="special">)</span> <span class="special">{</span> | |
113 | <span class="identifier">channel_</span><span class="special">-></span><span class="identifier">close</span><span class="special">();</span> | |
114 | <span class="special">}</span> | |
115 | <span class="special">}</span> | |
116 | ||
117 | <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">channel_op_status</span> <span class="identifier">push</span><span class="special">(</span> <span class="identifier">T</span> <span class="special">&&</span> <span class="identifier">va</span><span class="special">)</span> <span class="special">{</span> | |
118 | <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">channel_op_status</span> <span class="identifier">ok</span> <span class="special">=</span> | |
119 | <span class="identifier">channel_</span><span class="special">-></span><span class="identifier">push</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">>(</span> <span class="identifier">va</span><span class="special">)</span> <span class="special">);</span> | |
120 | <span class="keyword">if</span> <span class="special">(</span> <span class="identifier">ok</span> <span class="special">==</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">channel_op_status</span><span class="special">::</span><span class="identifier">success</span> <span class="special">&&</span> | |
121 | <span class="special">--</span><span class="identifier">limit_</span> <span class="special">==</span> <span class="number">0</span><span class="special">)</span> <span class="special">{</span> | |
122 | <span class="comment">// after the 'limit_'th successful push, close the channel</span> | |
123 | <span class="identifier">channel_</span><span class="special">-></span><span class="identifier">close</span><span class="special">();</span> | |
124 | <span class="special">}</span> | |
125 | <span class="keyword">return</span> <span class="identifier">ok</span><span class="special">;</span> | |
126 | <span class="special">}</span> | |
127 | ||
128 | <span class="keyword">private</span><span class="special">:</span> | |
129 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span> <span class="special">></span> <span class="identifier">channel_</span><span class="special">;</span> | |
130 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">limit_</span><span class="special">;</span> | |
131 | <span class="special">};</span> | |
132 | </pre> | |
133 | <p> | |
134 | </p> | |
135 | <p> | |
136 | <a name="wait_all_values_source"></a>Armed with <code class="computeroutput"><span class="identifier">nchannel</span><span class="special"><></span></code>, we can implement <code class="computeroutput"><span class="identifier">wait_all_values_source</span><span class="special">()</span></code>. | |
137 | It starts just like <a class="link" href="../when_any/when_any__return_value.html#wait_first_value"><code class="computeroutput"><span class="identifier">wait_first_value</span><span class="special">()</span></code></a>. The difference is that we wrap | |
138 | the <code class="computeroutput"><span class="identifier">unbounded_channel</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> | |
139 | with an <code class="computeroutput"><span class="identifier">nchannel</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> | |
140 | to pass to the producer fibers. | |
141 | </p> | |
142 | <p> | |
143 | Then, of course, instead of popping the first value, closing the channel | |
144 | and returning it, we simply return the <code class="computeroutput"><span class="identifier">shared_ptr</span><span class="special"><</span><span class="identifier">unbounded_channel</span><span class="special"><</span><span class="identifier">T</span><span class="special">>></span></code>. | |
145 | </p> | |
146 | <p> | |
147 | </p> | |
148 | <pre class="programlisting"><span class="comment">// Return a shared_ptr<unbounded_channel<T>> from which the caller can</span> | |
149 | <span class="comment">// retrieve each new result as it arrives, until 'closed'.</span> | |
150 | <span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">Fn</span><span class="special">,</span> <span class="keyword">typename</span> <span class="special">...</span> <span class="identifier">Fns</span> <span class="special">></span> | |
151 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">result_of</span><span class="special"><</span> <span class="identifier">Fn</span><span class="special">()</span> <span class="special">>::</span><span class="identifier">type</span> <span class="special">></span> <span class="special">></span> | |
152 | <span class="identifier">wait_all_values_source</span><span class="special">(</span> <span class="identifier">Fn</span> <span class="special">&&</span> <span class="identifier">function</span><span class="special">,</span> <span class="identifier">Fns</span> <span class="special">&&</span> <span class="special">...</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">{</span> | |
153 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">count</span><span class="special">(</span> <span class="number">1</span> <span class="special">+</span> <span class="keyword">sizeof</span> <span class="special">...</span> <span class="special">(</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">);</span> | |
154 | <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">result_of</span><span class="special"><</span> <span class="identifier">Fn</span><span class="special">()</span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">return_t</span><span class="special">;</span> | |
155 | <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</span><span class="special"><</span> <span class="identifier">return_t</span> <span class="special">></span> <span class="identifier">channel_t</span><span class="special">;</span> | |
156 | <span class="comment">// make the channel</span> | |
157 | <span class="keyword">auto</span> <span class="identifier">channelp</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">make_shared</span><span class="special"><</span> <span class="identifier">channel_t</span> <span class="special">>()</span> <span class="special">);</span> | |
158 | <span class="comment">// and make an nchannel facade to close it after 'count' items</span> | |
159 | <span class="keyword">auto</span> <span class="identifier">ncp</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">make_shared</span><span class="special"><</span> <span class="identifier">nchannel</span><span class="special"><</span> <span class="identifier">return_t</span> <span class="special">></span> <span class="special">>(</span> <span class="identifier">channelp</span><span class="special">,</span> <span class="identifier">count</span><span class="special">)</span> <span class="special">);</span> | |
160 | <span class="comment">// pass that nchannel facade to all the relevant fibers</span> | |
161 | <span class="identifier">wait_all_values_impl</span><span class="special"><</span> <span class="identifier">return_t</span> <span class="special">>(</span> <span class="identifier">ncp</span><span class="special">,</span> | |
162 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span> <span class="identifier">Fn</span> <span class="special">>(</span> <span class="identifier">function</span><span class="special">),</span> | |
163 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span> <span class="identifier">Fns</span> <span class="special">>(</span> <span class="identifier">functions</span><span class="special">)</span> <span class="special">...</span> <span class="special">);</span> | |
164 | <span class="comment">// then return the channel for consumer</span> | |
165 | <span class="keyword">return</span> <span class="identifier">channelp</span><span class="special">;</span> | |
166 | <span class="special">}</span> | |
167 | </pre> | |
168 | <p> | |
169 | </p> | |
170 | <p> | |
171 | For example: | |
172 | </p> | |
173 | <p> | |
174 | </p> | |
175 | <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">unbounded_channel</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="special">></span> <span class="identifier">channel</span> <span class="special">=</span> | |
176 | <span class="identifier">wait_all_values_source</span><span class="special">(</span> | |
177 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wavs_third"</span><span class="special">,</span> <span class="number">150</span><span class="special">);</span> <span class="special">},</span> | |
178 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wavs_second"</span><span class="special">,</span> <span class="number">100</span><span class="special">);</span> <span class="special">},</span> | |
179 | <span class="special">[](){</span> <span class="keyword">return</span> <span class="identifier">sleeper</span><span class="special">(</span><span class="string">"wavs_first"</span><span class="special">,</span> <span class="number">50</span><span class="special">);</span> <span class="special">});</span> | |
180 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">value</span><span class="special">;</span> | |
181 | <span class="keyword">while</span> <span class="special">(</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">channel_op_status</span><span class="special">::</span><span class="identifier">success</span> <span class="special">==</span> <span class="identifier">channel</span><span class="special">-></span><span class="identifier">pop</span><span class="special">(</span><span class="identifier">value</span><span class="special">)</span> <span class="special">)</span> <span class="special">{</span> | |
182 | <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"wait_all_values_source() => '"</span> <span class="special"><<</span> <span class="identifier">value</span> | |
183 | <span class="special"><<</span> <span class="string">"'"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> | |
184 | <span class="special">}</span> | |
185 | </pre> | |
186 | <p> | |
187 | </p> | |
188 | <p> | |
189 | <a name="wait_all_values_impl"></a><code class="computeroutput"><span class="identifier">wait_all_values_impl</span><span class="special">()</span></code> really is just like <a class="link" href="../when_any/when_any__return_value.html#wait_first_value_impl"><code class="computeroutput"><span class="identifier">wait_first_value_impl</span><span class="special">()</span></code></a> | |
190 | except for the use of <code class="computeroutput"><span class="identifier">nchannel</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> rather than <code class="computeroutput"><span class="identifier">unbounded_channel</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code>: | |
191 | </p> | |
192 | <p> | |
193 | </p> | |
194 | <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Fn</span> <span class="special">></span> | |
195 | <span class="keyword">void</span> <span class="identifier">wait_all_values_impl</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span> <span class="identifier">nchannel</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span> <span class="special">></span> <span class="identifier">channel</span><span class="special">,</span> | |
196 | <span class="identifier">Fn</span> <span class="special">&&</span> <span class="identifier">function</span><span class="special">)</span> <span class="special">{</span> | |
197 | <span class="identifier">boost</span><span class="special">::</span><span class="identifier">fibers</span><span class="special">::</span><span class="identifier">fiber</span><span class="special">(</span> <span class="special">[</span><span class="identifier">channel</span><span class="special">,</span> <span class="identifier">function</span><span class="special">](){</span> | |
198 | <span class="identifier">channel</span><span class="special">-></span><span class="identifier">push</span><span class="special">(</span><span class="identifier">function</span><span class="special">());</span> | |
199 | <span class="special">}).</span><span class="identifier">detach</span><span class="special">();</span> | |
200 | <span class="special">}</span> | |
201 | </pre> | |
202 | <p> | |
203 | </p> | |
204 | <div class="footnotes"> | |
205 | <br><hr width="100" align="left"> | |
206 | <div class="footnote"><p><sup>[<a name="ftn.fiber.when_any.when_all_functionality.when_all__return_values.f0" href="#fiber.when_any.when_all_functionality.when_all__return_values.f0" class="para">6</a>] </sup> | |
207 | We could have used either <a class="link" href="../../synchronization/channels.html#class_bounded_channel"><code class="computeroutput">bounded_channel<></code></a> or | |
208 | <a class="link" href="../../synchronization/channels.html#class_unbounded_channel"><code class="computeroutput">unbounded_channel<></code></a>. We chose <code class="computeroutput"><span class="identifier">unbounded_channel</span><span class="special"><></span></code> | |
209 | on the assumption that its simpler semantics imply a cheaper implementation. | |
210 | </p></div> | |
211 | </div> | |
212 | </div> | |
213 | <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> | |
214 | <td align="left"></td> | |
215 | <td align="right"><div class="copyright-footer">Copyright © 2013 Oliver Kowalke<p> | |
216 | Distributed under the Boost Software License, Version 1.0. (See accompanying | |
217 | 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>) | |
218 | </p> | |
219 | </div></td> | |
220 | </tr></table> | |
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