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make single_view random access

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[SVN r72977]
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Eric Niebler
2011-07-08 19:42:35 +00:00
parent 0a54764a6a
commit f27ed26e44
276 changed files with 4030 additions and 4061 deletions
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doc/html/fusion/algorithm.html
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@ -46,20 +46,18 @@
</dl></dd>
</dl></div>
<a name="fusion.algorithm.lazy_evaluation"></a><h4>
<a name="id1017942"></a>
<a name="fusion.algorithm.lazy_evaluation-heading"></a>
<a class="link" href="algorithm.html#fusion.algorithm.lazy_evaluation">Lazy Evaluation</a>
</h4>
<p>
Unlike <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, Fusion
algorithms are lazy
<sup>[<a name="id1017958" href="#ftn.id1017958" class="footnote">10</a>]</sup>
and non sequence-type preserving
<sup>[<a name="id1017986" href="#ftn.id1017986" class="footnote">11</a>]</sup>
. This is by design. Runtime efficiency is given a high priority. Like <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, and unlike <a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>, fusion
algorithms are mostly functional in nature such that algorithms are non mutating
(no side effects). However, due to the high cost of returning full sequences
such as vectors and lists, <span class="emphasis"><em>Views</em></span> are returned from Fusion
algorithms instead. For example, the <a class="link" href="algorithm/transformation/functions/transform.html" title="transform"><code class="computeroutput"><span class="identifier">transform</span></code></a> algorithm does not actually
algorithms are lazy<sup>[<a name="id1025231" href="#ftn.id1025231" class="footnote">10</a>]</sup> and non sequence-type preserving <sup>[<a name="id1025259" href="#ftn.id1025259" class="footnote">11</a>]</sup>. This is by design. Runtime efficiency is given a high priority.
Like <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, and
unlike <a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>,
fusion algorithms are mostly functional in nature such that algorithms are
non mutating (no side effects). However, due to the high cost of returning
full sequences such as vectors and lists, <span class="emphasis"><em>Views</em></span> are returned
from Fusion algorithms instead. For example, the <a class="link" href="algorithm/transformation/functions/transform.html" title="transform"><code class="computeroutput"><span class="identifier">transform</span></code></a> algorithm does not actually
return a transformed version of the original sequence. <a class="link" href="algorithm/transformation/functions/transform.html" title="transform"><code class="computeroutput"><span class="identifier">transform</span></code></a> returns a <a class="link" href="view/transform_view.html" title="transform_view"><code class="computeroutput"><span class="identifier">transform_view</span></code></a>. This view holds a
reference to the original sequence plus the transform function. Iteration over
the <a class="link" href="view/transform_view.html" title="transform_view"><code class="computeroutput"><span class="identifier">transform_view</span></code></a>
@ -68,7 +66,7 @@
as we want without incurring a high runtime penalty.
</p>
<a name="fusion.algorithm.sequence_extension"></a><h4>
<a name="id1018054"></a>
<a name="fusion.algorithm.sequence_extension-heading"></a>
<a class="link" href="algorithm.html#fusion.algorithm.sequence_extension">Sequence Extension</a>
</h4>
<p>
@ -91,7 +89,7 @@
functions to convert back to the original sequence type.
</p>
<a name="fusion.algorithm.header"></a><h4>
<a name="id1018165"></a>
<a name="fusion.algorithm.header-heading"></a>
<a class="link" href="algorithm.html#fusion.algorithm.header">Header</a>
</h4>
<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">hpp</span><span class="special">&gt;</span>
@ -99,15 +97,15 @@
</pre>
<div class="footnotes">
<br><hr width="100" align="left">
<div class="footnote"><p><sup>[<a name="ftn.id1017958" href="#id1017958" class="para">10</a>] </sup>
Except for some special cases such as <a class="link" href="algorithm/iteration/functions/for_each.html" title="for_each"><code class="computeroutput"><span class="identifier">for_each</span></code></a> and <a class="link" href="algorithm/auxiliary/functions/copy.html" title="copy"><code class="computeroutput"><span class="identifier">copy</span></code></a> which are inherently imperative
algorithms.
</p></div>
<div class="footnote"><p><sup>[<a name="ftn.id1017986" href="#id1017986" class="para">11</a>] </sup>
What does that mean? It means that when you operate on a sequence through
a Fusion algorithm that returns a sequence, the sequence returned may not
be of the same class as the original
</p></div>
<div class="footnote"><p><sup>[<a name="ftn.id1025231" href="#id1025231" class="para">10</a>] </sup>
Except for some special cases such as <a class="link" href="algorithm/iteration/functions/for_each.html" title="for_each"><code class="computeroutput"><span class="identifier">for_each</span></code></a> and <a class="link" href="algorithm/auxiliary/functions/copy.html" title="copy"><code class="computeroutput"><span class="identifier">copy</span></code></a> which are inherently imperative
algorithms.
</p></div>
<div class="footnote"><p><sup>[<a name="ftn.id1025259" href="#id1025259" class="para">11</a>] </sup>
What does that mean? It means that when you operate on a sequence through
a Fusion algorithm that returns a sequence, the sequence returned may not
be of the same class as the original
</p></div>
</div>
</div>
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