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26 <div class=
"titlepage"><div><div><h4 class=
"title">
27 <a name=
"fiber.when_any.when_all_functionality.when_all_until_first_exception"></a><a class=
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"when_all_until_first_exception.html" title=
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28 until first exception
</a>
29 </h4></div></div></div>
31 Naturally, just as with
<a class=
"link" href=
"../when_any/when_any__produce_first_outcome__whether_result_or_exception.html#wait_first_outcome"><code class=
"computeroutput"><span class=
"identifier">wait_first_outcome
</span><span class=
"special">()
</span></code></a>,
32 we can elaborate
<a class=
"link" href=
"when_all__return_values.html#wait_all_values"><code class=
"computeroutput"><span class=
"identifier">wait_all_values
</span><span class=
"special">()
</span></code></a> and
<a class=
"link" href=
"when_all__return_values.html#wait_all_values_source"><code class=
"computeroutput"><span class=
"identifier">wait_all_values_source
</span><span class=
"special">()
</span></code></a>
33 by passing
<code class=
"computeroutput"><span class=
"identifier">future
</span><span class=
"special"><</span>
34 <span class=
"identifier">T
</span> <span class=
"special">></span></code>
35 instead of plain
<code class=
"computeroutput"><span class=
"identifier">T
</span></code>.
38 <a name=
"wait_all_until_error"></a><code class=
"computeroutput"><span class=
"identifier">wait_all_until_error
</span><span class=
"special">()
</span></code> pops that
<code class=
"computeroutput"><span class=
"identifier">future
</span><span class=
"special"><</span> <span class=
"identifier">T
</span> <span class=
"special">></span></code> and calls its
<a class=
"link" href=
"../../synchronization/futures/future.html#future_get"><code class=
"computeroutput">future::get()
</code></a>:
42 <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>
43 <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>
44 <span class=
"identifier">wait_all_until_error
</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>
45 <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>
46 <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>
47 <span class=
"keyword">typedef
</span> <span class=
"keyword">typename
</span> <span class=
"identifier">boost
</span><span class=
"special">::
</span><span class=
"identifier">fibers
</span><span class=
"special">::
</span><span class=
"identifier">future
</span><span class=
"special"><</span> <span class=
"identifier">return_t
</span> <span class=
"special">></span> <span class=
"identifier">future_t
</span><span class=
"special">;
</span>
48 <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>
49 <span class=
"identifier">vector_t
</span> <span class=
"identifier">results
</span><span class=
"special">;
</span>
50 <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>
52 <span class=
"comment">// get channel
</span>
53 <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">shared_ptr
</span><span class=
"special"><</span>
54 <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">future_t
</span> <span class=
"special">></span> <span class=
"special">></span> <span class=
"identifier">channel
</span><span class=
"special">(
</span>
55 <span class=
"identifier">wait_all_until_error_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>
56 <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> <span class=
"special">);
</span>
57 <span class=
"comment">// fill results vector
</span>
58 <span class=
"identifier">future_t
</span> <span class=
"identifier">future
</span><span class=
"special">;
</span>
59 <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">future
</span><span class=
"special">)
</span> <span class=
"special">)
</span> <span class=
"special">{
</span>
60 <span class=
"identifier">results
</span><span class=
"special">.
</span><span class=
"identifier">push_back
</span><span class=
"special">(
</span> <span class=
"identifier">future
</span><span class=
"special">.
</span><span class=
"identifier">get
</span><span class=
"special">()
</span> <span class=
"special">);
</span>
61 <span class=
"special">}
</span>
62 <span class=
"comment">// return vector to caller
</span>
63 <span class=
"keyword">return
</span> <span class=
"identifier">results
</span><span class=
"special">;
</span>
64 <span class=
"special">}
</span>
73 <pre class=
"programlisting"><span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">string
</span> <span class=
"identifier">thrown
</span><span class=
"special">;
</span>
74 <span class=
"keyword">try
</span> <span class=
"special">{
</span>
75 <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> <span class=
"identifier">wait_all_until_error
</span><span class=
"special">(
</span>
76 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"waue_late"</span><span class=
"special">,
</span> <span class=
"number">150</span><span class=
"special">);
</span> <span class=
"special">},
</span>
77 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"waue_middle"</span><span class=
"special">,
</span> <span class=
"number">100</span><span class=
"special">,
</span> <span class=
"keyword">true
</span><span class=
"special">);
</span> <span class=
"special">},
</span>
78 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"waue_early"</span><span class=
"special">,
</span> <span class=
"number">50</span><span class=
"special">);
</span> <span class=
"special">});
</span>
79 <span class=
"special">}
</span> <span class=
"keyword">catch
</span> <span class=
"special">(
</span> <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">exception
</span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"identifier">e
</span><span class=
"special">)
</span> <span class=
"special">{
</span>
80 <span class=
"identifier">thrown
</span> <span class=
"special">=
</span> <span class=
"identifier">e
</span><span class=
"special">.
</span><span class=
"identifier">what
</span><span class=
"special">();
</span>
81 <span class=
"special">}
</span>
82 <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">cout
</span> <span class=
"special"><<</span> <span class=
"string">"wait_all_until_error(fail) threw '"</span> <span class=
"special"><<</span> <span class=
"identifier">thrown
</span>
83 <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>
88 <a name=
"wait_all_until_error_source"></a>Naturally this complicates the
89 API for
<code class=
"computeroutput"><span class=
"identifier">wait_all_until_error_source
</span><span class=
"special">()
</span></code>. The caller must both retrieve a
<code class=
"computeroutput"><span class=
"identifier">future
</span><span class=
"special"><</span>
90 <span class=
"identifier">T
</span> <span class=
"special">></span></code>
91 and call its
<code class=
"computeroutput"><span class=
"identifier">get
</span><span class=
"special">()
</span></code>
92 method. It would, of course, be possible to return a fa
çade over the consumer
93 end of the channel that would implicitly perform the
<code class=
"computeroutput"><span class=
"identifier">get
</span><span class=
"special">()
</span></code> and return a simple
<code class=
"computeroutput"><span class=
"identifier">T
</span></code>
97 The implementation is just as you would expect. Notice, however, that we
98 can reuse
<a class=
"link" href=
"../when_any/when_any__produce_first_outcome__whether_result_or_exception.html#wait_first_outcome_impl"><code class=
"computeroutput"><span class=
"identifier">wait_first_outcome_impl
</span><span class=
"special">()
</span></code></a>, passing the
<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>.
102 <pre class=
"programlisting"><span class=
"comment">// Return a shared_ptr
<unbounded_channel
<future
<T
>>> from which the caller can
</span>
103 <span class=
"comment">// get() each new result as it arrives, until 'closed'.
</span>
104 <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>
105 <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">shared_ptr
</span><span class=
"special"><</span>
106 <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>
107 <span class=
"identifier">boost
</span><span class=
"special">::
</span><span class=
"identifier">fibers
</span><span class=
"special">::
</span><span class=
"identifier">future
</span><span class=
"special"><</span>
108 <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> <span class=
"special">></span>
109 <span class=
"identifier">wait_all_until_error_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>
110 <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>
111 <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>
112 <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">future
</span><span class=
"special"><</span> <span class=
"identifier">return_t
</span> <span class=
"special">></span> <span class=
"identifier">future_t
</span><span class=
"special">;
</span>
113 <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">future_t
</span> <span class=
"special">></span> <span class=
"identifier">channel_t
</span><span class=
"special">;
</span>
114 <span class=
"comment">// make the channel
</span>
115 <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>
116 <span class=
"comment">// and make an nchannel facade to close it after 'count' items
</span>
117 <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">future_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>
118 <span class=
"comment">// pass that nchannel facade to all the relevant fibers
</span>
119 <span class=
"identifier">wait_first_outcome_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>
120 <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>
121 <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>
122 <span class=
"comment">// then return the channel for consumer
</span>
123 <span class=
"keyword">return
</span> <span class=
"identifier">channelp
</span><span class=
"special">;
</span>
124 <span class=
"special">}
</span>
133 <pre class=
"programlisting"><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">future
</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">future_t
</span><span class=
"special">;
</span>
134 <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">future_t
</span> <span class=
"special">></span> <span class=
"special">></span> <span class=
"identifier">channel
</span> <span class=
"special">=
</span>
135 <span class=
"identifier">wait_all_until_error_source
</span><span class=
"special">(
</span>
136 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"wauess_third"</span><span class=
"special">,
</span> <span class=
"number">150</span><span class=
"special">);
</span> <span class=
"special">},
</span>
137 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"wauess_second"</span><span class=
"special">,
</span> <span class=
"number">100</span><span class=
"special">);
</span> <span class=
"special">},
</span>
138 <span class=
"special">[](){
</span> <span class=
"keyword">return
</span> <span class=
"identifier">sleeper
</span><span class=
"special">(
</span><span class=
"string">"wauess_first"</span><span class=
"special">,
</span> <span class=
"number">50</span><span class=
"special">);
</span> <span class=
"special">});
</span>
139 <span class=
"identifier">future_t
</span> <span class=
"identifier">future
</span><span class=
"special">;
</span>
140 <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">future
</span><span class=
"special">)
</span> <span class=
"special">)
</span> <span class=
"special">{
</span>
141 <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">string
</span> <span class=
"identifier">value
</span><span class=
"special">(
</span> <span class=
"identifier">future
</span><span class=
"special">.
</span><span class=
"identifier">get
</span><span class=
"special">()
</span> <span class=
"special">);
</span>
142 <span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">cout
</span> <span class=
"special"><<</span> <span class=
"string">"wait_all_until_error_source(success) => '"</span> <span class=
"special"><<</span> <span class=
"identifier">value
</span>
143 <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>
144 <span class=
"special">}
</span>
149 <table xmlns:
rev=
"http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width=
"100%"><tr>
150 <td align=
"left"></td>
151 <td align=
"right"><div class=
"copyright-footer">Copyright
© 2013 Oliver Kowalke
<p>
152 Distributed under the Boost Software License, Version
1.0. (See accompanying
153 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>)
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"spirit-nav">
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