mirror of
https://github.com/boostorg/iterator.git
synced 2025-07-20 16:12:10 +02:00
Some progress on indirect_iterator
[SVN r21710]
This commit is contained in:
Dave Abrahams
@ -57,7 +57,7 @@ texcrap = *.mpx *.log *.aux *.blg *-print.brf *-print.tex *.out
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mpxcrap = mpxerr.tex mpxerr.pdf
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generated = *.out *.[0-9] *.[0-9][0-9] *.bbl *.brf \
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*.mp *.mmp *.pdf .depend *.ps TMP-*.pdf *.ftoc\
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*.mp *.mmp *.pdf *.ps TMP-*.pdf *.ftoc\
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${PRINTZIP} ${SLIDEZIP} ${GENFILE} ${DEPENDFILES} \
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${texcrap} ${mpxcrap} ${CUTFOILS} $(strip $(wildcard *---*.tex))
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@ -211,7 +211,7 @@ clean:
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${RMRF} ${generated}
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# ... Target: create dependencies
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depend: .depend .depend-rst
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depend: .depend-rst
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# ... Target: dependency file (parse TEXFILES for multiinclude and includegraphics)
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.depend: GNUmakefile ${TEXFILES}
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@ -226,11 +226,11 @@ depend: .depend .depend-rst
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${RMRF} $@
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@for t in ${RSTSTEMS} ; do \
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${ECHO} "Scanning $$t.rst"; \
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${PERL} -e 'my $$target = shift @ARGV;' -e 'while (<>) { /^\.\. include::\s+(.*)/ && print "$$target: $$1\n";}' $$t.html < $$t.rst >> $@; \
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${PERL} -e 'my $$target = shift @ARGV;' -e 'while (<>) { /^\.\. include::\s+(.*)/ && print "$$target: $$1\n";}' $$t.tex < $$t.rst >> $@; \
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${PERL} -e 'my $$target = shift @ARGV;' -e 'while (<>) { /^\.\. (include|image)::\s+(.*)/ && print "$$target: $$2\n";}' $$t.html < $$t.rst >> $@; \
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${PERL} -e 'my $$target = shift @ARGV;' -e 'while (<>) { /^\.\. (include|image)::\s+(.*)/ && print "$$target: $$2\n";}' $$t.tex < $$t.rst >> $@; \
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done
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# ... include dependency files
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-include .depend
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# -include .depend
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-include .depend-rst
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@ -7,7 +7,7 @@
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<title>Iterator Facade and Adaptor</title>
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<meta name="author" content="David Abrahams, Jeremy Siek, Thomas Witt" />
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<meta name="organization" content="Boost Consulting, Indiana University Open Systems Lab, University of Hanover Institute for Transport Railway Operation and Construction" />
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<meta name="date" content="2004-01-12" />
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<meta name="date" content="2004-01-13" />
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<link rel="stylesheet" href="default.css" type="text/css" />
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</head>
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<body>
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@ -26,7 +26,7 @@
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Lab</a>, University of Hanover <a class="last reference" href="http://www.ive.uni-hannover.de">Institute for Transport
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Railway Operation and Construction</a></td></tr>
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<tr><th class="docinfo-name">Date:</th>
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<td>2004-01-12</td></tr>
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<td>2004-01-13</td></tr>
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<tr class="field"><th class="docinfo-name">Number:</th><td class="field-body">This is a revised version of <a class="reference" href="http://anubis.dkuug.dk/jtc1/sc22/wg21/docs/papers/2003/n1530.html">N1530</a>=03-0113, which was
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accepted for Technical Report 1 by the C++ standard
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committee's library working group.</td>
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@ -802,8 +802,7 @@ Iterator</td>
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<div class="section" id="iterator-facade-iterator-category">
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<h3><a class="toc-backref" href="#id30" name="iterator-facade-iterator-category"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></h3>
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<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade<X,V,R,C,D></span></tt>
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is a type which satisfies the following conditions:</p>
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<blockquote>
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satisfies the following conditions:</p>
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<ul>
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<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
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<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
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@ -845,7 +844,9 @@ convertible, and not to any more-derived traversal tag type.</p>
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</ul>
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</li>
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||||
</ul>
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</blockquote>
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||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
</div>
|
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<div class="section" id="iterator-facade-operations">
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<h3><a class="toc-backref" href="#id31" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h3>
|
||||
@ -1410,37 +1411,72 @@ if (Difference is use_default)
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||||
else
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||||
typedef Difference difference_type;
|
||||
</pre>
|
||||
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt> then
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>. Otherwise
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is a type convertible to the tag determined by
|
||||
the following algorithm. Let <tt class="literal"><span class="pre">C</span></tt> be <tt class="literal"><span class="pre">traversal_category<Iterator>::type</span></tt>.</p>
|
||||
<p><tt class="literal"><span class="pre">iterator_category</span></tt> satisfies the following conditions, where
|
||||
<tt class="literal"><span class="pre">R</span></tt> is <tt class="literal"><span class="pre">reference</span></tt> and <tt class="literal"><span class="pre">V</span></tt> is <tt class="literal"><span class="pre">value_type</span></tt>, and where: if
|
||||
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is
|
||||
<tt class="literal"><span class="pre">iterator_traversal<Iterator>::type</span></tt> and otherwise <tt class="literal"><span class="pre">C</span></tt> is
|
||||
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>:</p>
|
||||
<blockquote>
|
||||
<ul>
|
||||
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
|
||||
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
|
||||
</li>
|
||||
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
|
||||
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
|
||||
</li>
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||||
<li><p class="first">Otherwise:</p>
|
||||
<ul>
|
||||
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
|
||||
category tag or tags given by the following algorithm, and
|
||||
not to any more-derived iterator category tag or tags:</p>
|
||||
<pre class="literal-block">
|
||||
if (reference is a reference to value_type) then
|
||||
if (C is convertible to random_access_traversal_tag) then
|
||||
if (R is a reference type
|
||||
&& C is convertible to forward_traversal_tag)
|
||||
{
|
||||
if (C is convertible to random_access_traversal_tag)
|
||||
random_access_iterator_tag
|
||||
else if (C is convertible to bidirectional_traversal_tag) then
|
||||
else if (C is convertible to bidirectional_traversal_tag)
|
||||
bidirectional_iterator_tag
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||||
else
|
||||
forward_iterator_tag
|
||||
}
|
||||
else
|
||||
{
|
||||
if (C is convertible to single_pass_traversal_tag
|
||||
&& R is convertible to V)
|
||||
input_iterator_tag
|
||||
else
|
||||
C
|
||||
}
|
||||
</pre>
|
||||
</li>
|
||||
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal<X>::type</span></tt> is convertible to the most
|
||||
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
|
||||
convertible, and not to any more-derived traversal tag type.</p>
|
||||
</li>
|
||||
</ul>
|
||||
</li>
|
||||
</ul>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
</blockquote>
|
||||
</div>
|
||||
<div class="section" id="indirect-iterator-requirements">
|
||||
<h4><a class="toc-backref" href="#id45" name="indirect-iterator-requirements"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></h4>
|
||||
<p>The <tt class="literal"><span class="pre">Iterator</span></tt> argument shall meet the requirements of Readable
|
||||
Iterator. The <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> argument shall be one of the
|
||||
standard iterator tags or <tt class="literal"><span class="pre">use_default</span></tt>. If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>
|
||||
is an iterator tag, the template parameter <tt class="literal"><span class="pre">Iterator</span></tt> argument shall
|
||||
meet the requirements corresponding to the iterator tag.</p>
|
||||
<p><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> argument shall be <tt class="literal"><span class="pre">use_default</span></tt> or it
|
||||
shall be convertible to one of the standard iterator or traversal
|
||||
tags. If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt>, it shall
|
||||
indicate the traversal category modeled by <tt class="literal"><span class="pre">Iterator</span></tt>. If</p>
|
||||
<p>The expression <tt class="literal"><span class="pre">*v</span></tt>, where <tt class="literal"><span class="pre">v</span></tt> is an object of type
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt>, must be a valid expression
|
||||
and must be convertible to <tt class="literal"><span class="pre">indirect_iterator::reference</span></tt>. Also
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt>, shall be valid
|
||||
expression and convertible to <tt class="literal"><span class="pre">reference</span></tt>. Also
|
||||
<tt class="literal"><span class="pre">indirect_iterator::reference</span></tt> must be convertible to
|
||||
<tt class="literal"><span class="pre">indirect_iterator::value</span></tt>. There are further requirements on the
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt> if the <tt class="literal"><span class="pre">Value</span></tt> parameter
|
||||
is not <tt class="literal"><span class="pre">use_default</span></tt>, as implied by the algorithm for deducing the
|
||||
default for the <tt class="literal"><span class="pre">value_type</span></tt> member.</p>
|
||||
<tt class="literal"><span class="pre">indirect_iterator::value</span></tt>. There are further requirements on
|
||||
the <tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt> if the <tt class="literal"><span class="pre">Value</span></tt>
|
||||
parameter is not <tt class="literal"><span class="pre">use_default</span></tt>, as implied by the algorithm for
|
||||
deducing the default for the <tt class="literal"><span class="pre">value_type</span></tt> member.</p>
|
||||
</div>
|
||||
<div class="section" id="indirect-iterator-models">
|
||||
<h4><a class="toc-backref" href="#id46" name="indirect-iterator-models"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></h4>
|
||||
@ -2436,7 +2472,6 @@ LocalWords: OtherIncrementable Coplien -->
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||||
<hr class="footer" />
|
||||
<div class="footer">
|
||||
<a class="reference" href="facade-and-adaptor.rst">View document source</a>.
|
||||
Generated on: 2004-01-13 20:19 UTC.
|
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Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
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</div>
|
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</body>
|
||||
|
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39
doc/facade_iterator_category.rst
Executable file
39
doc/facade_iterator_category.rst
Executable file
@ -0,0 +1,39 @@
|
||||
* if ``C`` is convertible to ``std::input_iterator_tag`` or
|
||||
``C`` is convertible to ``std::output_iterator_tag``,
|
||||
``iterator_category`` is the same as ``C``.
|
||||
|
||||
* Otherwise, if ``C`` is not convertible to
|
||||
``incrementable_traversal_tag``, the program is ill-formed
|
||||
|
||||
* Otherwise:
|
||||
|
||||
- ``iterator_category`` is convertible to the iterator
|
||||
category tag or tags given by the following algorithm, and
|
||||
not to any more-derived iterator category tag or tags::
|
||||
|
||||
if (R is a reference type
|
||||
&& C is convertible to forward_traversal_tag)
|
||||
{
|
||||
if (C is convertible to random_access_traversal_tag)
|
||||
random_access_iterator_tag
|
||||
else if (C is convertible to bidirectional_traversal_tag)
|
||||
bidirectional_iterator_tag
|
||||
else
|
||||
forward_iterator_tag
|
||||
}
|
||||
else
|
||||
{
|
||||
if (C is convertible to single_pass_traversal_tag
|
||||
&& R is convertible to V)
|
||||
input_iterator_tag
|
||||
else
|
||||
C
|
||||
}
|
||||
|
||||
- ``iterator_traversal<X>::type`` is convertible to the most
|
||||
derived traversal tag type to which ``C`` is also
|
||||
convertible, and not to any more-derived traversal tag type.
|
||||
|
||||
.. Copyright David Abrahams 2004. Use, modification and distribution is
|
||||
.. subject to the Boost Software License, Version 1.0. (See accompanying
|
||||
.. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
||||
@ -140,6 +140,9 @@ underlying sequence. This component also replaces the old
|
||||
<div class="section" id="traits">
|
||||
<h2><a class="toc-backref" href="#id10" name="traits">Traits</a></h2>
|
||||
<ul class="simple">
|
||||
<li><a class="reference" href="pointee.html"><tt class="literal"><span class="pre">pointee.hpp</span></tt></a>: Provides the capability to deduce the referent types
|
||||
of pointers, smart pointers and iterators in generic code. Used
|
||||
in <tt class="literal"><span class="pre">indirect_iterator</span></tt>.</li>
|
||||
<li><a class="reference" href="iterator_traits.html"><tt class="literal"><span class="pre">iterator_traits.hpp</span></tt></a>: Provides <a class="reference" href="../../mpl/doc/index.html">MPL</a>-compatible metafunctions which
|
||||
retrieve an iterator's traits. Also corrects for the deficiencies
|
||||
of broken implementations of <tt class="literal"><span class="pre">std::iterator_traits</span></tt>.</li>
|
||||
@ -226,7 +229,7 @@ LocalWords: TraversalTag typename lvalues DWA Hmm JGS -->
|
||||
<hr class="footer" />
|
||||
<div class="footer">
|
||||
<a class="reference" href="index.rst">View document source</a>.
|
||||
Generated on: 2004-01-13 14:25 UTC.
|
||||
Generated on: 2004-01-13.
|
||||
Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
|
||||
</div>
|
||||
</body>
|
||||
|
||||
@ -169,6 +169,10 @@ iterator templates based on the Boost `iterator facade and adaptor`_.
|
||||
Traits
|
||||
------
|
||||
|
||||
* |pointee|_: Provides the capability to deduce the referent types
|
||||
of pointers, smart pointers and iterators in generic code. Used
|
||||
in |indirect|.
|
||||
|
||||
* |iterator_traits|_: Provides MPL_\ -compatible metafunctions which
|
||||
retrieve an iterator's traits. Also corrects for the deficiencies
|
||||
of broken implementations of ``std::iterator_traits``.
|
||||
@ -176,6 +180,9 @@ Traits
|
||||
* |interoperable|_: Provides an MPL_\ -compatible metafunction for
|
||||
testing iterator interoperability
|
||||
|
||||
.. |pointee| replace:: ``pointee.hpp``
|
||||
.. _pointee: pointee.html
|
||||
|
||||
.. |iterator_traits| replace:: ``iterator_traits.hpp``
|
||||
.. _iterator_traits: iterator_traits.html
|
||||
|
||||
|
||||
@ -125,37 +125,72 @@ if (Difference is use_default)
|
||||
else
|
||||
typedef Difference difference_type;
|
||||
</pre>
|
||||
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt> then
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>. Otherwise
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is a type convertible to the tag determined by
|
||||
the following algorithm. Let <tt class="literal"><span class="pre">C</span></tt> be <tt class="literal"><span class="pre">traversal_category<Iterator>::type</span></tt>.</p>
|
||||
<p><tt class="literal"><span class="pre">iterator_category</span></tt> satisfies the following conditions, where
|
||||
<tt class="literal"><span class="pre">R</span></tt> is <tt class="literal"><span class="pre">reference</span></tt> and <tt class="literal"><span class="pre">V</span></tt> is <tt class="literal"><span class="pre">value_type</span></tt>, and where: if
|
||||
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is
|
||||
<tt class="literal"><span class="pre">iterator_traversal<Iterator>::type</span></tt> and otherwise <tt class="literal"><span class="pre">C</span></tt> is
|
||||
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>:</p>
|
||||
<blockquote>
|
||||
<ul>
|
||||
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
|
||||
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
|
||||
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
|
||||
</li>
|
||||
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
|
||||
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
|
||||
</li>
|
||||
<li><p class="first">Otherwise:</p>
|
||||
<ul>
|
||||
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
|
||||
category tag or tags given by the following algorithm, and
|
||||
not to any more-derived iterator category tag or tags:</p>
|
||||
<pre class="literal-block">
|
||||
if (reference is a reference to value_type) then
|
||||
if (C is convertible to random_access_traversal_tag) then
|
||||
if (R is a reference type
|
||||
&& C is convertible to forward_traversal_tag)
|
||||
{
|
||||
if (C is convertible to random_access_traversal_tag)
|
||||
random_access_iterator_tag
|
||||
else if (C is convertible to bidirectional_traversal_tag) then
|
||||
else if (C is convertible to bidirectional_traversal_tag)
|
||||
bidirectional_iterator_tag
|
||||
else
|
||||
forward_iterator_tag
|
||||
}
|
||||
else
|
||||
{
|
||||
if (C is convertible to single_pass_traversal_tag
|
||||
&& R is convertible to V)
|
||||
input_iterator_tag
|
||||
else
|
||||
C
|
||||
}
|
||||
</pre>
|
||||
</li>
|
||||
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal<X>::type</span></tt> is convertible to the most
|
||||
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
|
||||
convertible, and not to any more-derived traversal tag type.</p>
|
||||
</li>
|
||||
</ul>
|
||||
</li>
|
||||
</ul>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
</blockquote>
|
||||
</div>
|
||||
<div class="section" id="indirect-iterator-requirements">
|
||||
<h1><a class="toc-backref" href="#id3" name="indirect-iterator-requirements"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></h1>
|
||||
<p>The <tt class="literal"><span class="pre">Iterator</span></tt> argument shall meet the requirements of Readable
|
||||
Iterator. The <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> argument shall be one of the
|
||||
standard iterator tags or <tt class="literal"><span class="pre">use_default</span></tt>. If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>
|
||||
is an iterator tag, the template parameter <tt class="literal"><span class="pre">Iterator</span></tt> argument shall
|
||||
meet the requirements corresponding to the iterator tag.</p>
|
||||
<p><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> argument shall be <tt class="literal"><span class="pre">use_default</span></tt> or it
|
||||
shall be convertible to one of the standard iterator or traversal
|
||||
tags. If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt>, it shall
|
||||
indicate the traversal category modeled by <tt class="literal"><span class="pre">Iterator</span></tt>. If</p>
|
||||
<p>The expression <tt class="literal"><span class="pre">*v</span></tt>, where <tt class="literal"><span class="pre">v</span></tt> is an object of type
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt>, must be a valid expression
|
||||
and must be convertible to <tt class="literal"><span class="pre">indirect_iterator::reference</span></tt>. Also
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt>, shall be valid
|
||||
expression and convertible to <tt class="literal"><span class="pre">reference</span></tt>. Also
|
||||
<tt class="literal"><span class="pre">indirect_iterator::reference</span></tt> must be convertible to
|
||||
<tt class="literal"><span class="pre">indirect_iterator::value</span></tt>. There are further requirements on the
|
||||
<tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt> if the <tt class="literal"><span class="pre">Value</span></tt> parameter
|
||||
is not <tt class="literal"><span class="pre">use_default</span></tt>, as implied by the algorithm for deducing the
|
||||
default for the <tt class="literal"><span class="pre">value_type</span></tt> member.</p>
|
||||
<tt class="literal"><span class="pre">indirect_iterator::value</span></tt>. There are further requirements on
|
||||
the <tt class="literal"><span class="pre">iterator_traits<Iterator>::value_type</span></tt> if the <tt class="literal"><span class="pre">Value</span></tt>
|
||||
parameter is not <tt class="literal"><span class="pre">use_default</span></tt>, as implied by the algorithm for
|
||||
deducing the default for the <tt class="literal"><span class="pre">value_type</span></tt> member.</p>
|
||||
</div>
|
||||
<div class="section" id="indirect-iterator-models">
|
||||
<h1><a class="toc-backref" href="#id4" name="indirect-iterator-models"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></h1>
|
||||
@ -327,7 +362,6 @@ a,b,c,d,e,f,g,
|
||||
<hr class="footer" />
|
||||
<div class="footer">
|
||||
<a class="reference" href="indirect_iterator.rst">View document source</a>.
|
||||
Generated on: 2004-01-13 19:54 UTC.
|
||||
Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
|
||||
</div>
|
||||
</body>
|
||||
|
||||
@ -66,52 +66,34 @@ following pseudo-code. We use the abbreviation
|
||||
else
|
||||
typedef Difference difference_type;
|
||||
|
||||
``iterator_category`` satisfies the following conditions, where
|
||||
``R`` is ``reference`` and ``V`` is ``value_type``, and where: if
|
||||
``CategoryOrTraversal`` is ``use_default``, ``C`` is
|
||||
``iterator_traversal<Iterator>::type`` and otherwise ``C`` is
|
||||
``CategoryOrTraversal``:
|
||||
|
||||
If ``CategoryOrTraversal`` is not ``use_default`` then
|
||||
``iterator_category`` is ``CategoryOrTraversal``. Otherwise
|
||||
``iterator_category`` is a type convertible to the tag determined by
|
||||
the following algorithm. Let ``C`` be ``traversal_category<Iterator>::type``.
|
||||
|
||||
::
|
||||
|
||||
if (reference is a reference to value_type) then
|
||||
if (C is convertible to random_access_traversal_tag) then
|
||||
random_access_iterator_tag
|
||||
else if (C is convertible to bidirectional_traversal_tag) then
|
||||
bidirectional_iterator_tag
|
||||
else
|
||||
forward_iterator_tag
|
||||
else
|
||||
input_iterator_tag
|
||||
|
||||
.. include:: facade_iterator_category.rst
|
||||
|
||||
``indirect_iterator`` requirements
|
||||
..................................
|
||||
|
||||
The ``Iterator`` argument shall meet the requirements of Readable
|
||||
Iterator. The ``CategoryOrTraversal`` argument shall be one of the
|
||||
standard iterator tags or ``use_default``. If ``CategoryOrTraversal``
|
||||
is an iterator tag, the template parameter ``Iterator`` argument shall
|
||||
meet the requirements corresponding to the iterator tag.
|
||||
|
||||
The expression ``*v``, where ``v`` is an object of type
|
||||
``iterator_traits<Iterator>::value_type``, must be a valid expression
|
||||
and must be convertible to ``indirect_iterator::reference``. Also
|
||||
``indirect_iterator::reference`` must be convertible to
|
||||
``indirect_iterator::value``. There are further requirements on the
|
||||
``iterator_traits<Iterator>::value_type`` if the ``Value`` parameter
|
||||
is not ``use_default``, as implied by the algorithm for deducing the
|
||||
default for the ``value_type`` member.
|
||||
``iterator_traits<Iterator>::value_type``, shall be valid
|
||||
expression and convertible to ``reference``. [Note: there are
|
||||
further requirements on the
|
||||
``iterator_traits<Iterator>::value_type`` if the ``Value``
|
||||
parameter is not ``use_default``, as implied by the algorithm for
|
||||
deducing the default for the ``value_type`` member.]
|
||||
|
||||
|
||||
``indirect_iterator`` models
|
||||
............................
|
||||
|
||||
If ``CategoryOrTraversal`` is a standard iterator tag,
|
||||
``indirect_iterator`` is a model of the iterator concept corresponding
|
||||
to the tag, otherwise ``indirect_iterator`` satisfies the requirements
|
||||
of the most refined standard traversal concept that is satisfied by
|
||||
the ``Iterator`` argument.
|
||||
``indirect_iterator`` is a model of the iterator concept
|
||||
corresponding to the tag. Otherwise, ``indirect_iterator``
|
||||
satisfies the requirements of the most refined standard traversal
|
||||
concept that is satisfied by the ``Iterator`` argument.
|
||||
|
||||
``indirect_iterator`` models Readable Iterator. If
|
||||
``indirect_iterator::reference(*v) = t`` is a valid expression (where
|
||||
|
||||
29
doc/indirect_reference_ref.rst
Executable file
29
doc/indirect_reference_ref.rst
Executable file
@ -0,0 +1,29 @@
|
||||
.. Copyright David Abrahams 2004. Use, modification and distribution is
|
||||
.. subject to the Boost Software License, Version 1.0. (See accompanying
|
||||
.. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
||||
|
||||
::
|
||||
|
||||
template <class Dereferenceable>
|
||||
struct indirect_reference
|
||||
{
|
||||
typedef /* see below */ type;
|
||||
};
|
||||
|
||||
:Requires: For an object ``x`` of type ``Dereferenceable``, ``*x``
|
||||
is well-formed. If ``++x`` is ill-formed it shall neither be
|
||||
ambiguous nor shall it violate access control, and
|
||||
``pointee<Dereferenceable>::type&`` shall be well-formed.
|
||||
Otherwise ``iterator_traits<Dereferenceable>::reference`` shall
|
||||
be well formed. [Note: These requirements need not apply to
|
||||
explicit or partial specializations of ``indirect_reference``]
|
||||
|
||||
``type`` is determined according to the following algorithm, where
|
||||
``x`` is an object of type ``Dereferenceable``::
|
||||
|
||||
if ( ++x is ill-formed )
|
||||
return ``pointee<Dereferenceable>::type&``
|
||||
else
|
||||
std::iterator_traits<Dereferenceable>::value_type
|
||||
|
||||
|
||||
@ -466,8 +466,7 @@ Iterator</td>
|
||||
<div class="section" id="iterator-facade-iterator-category">
|
||||
<h2><a class="toc-backref" href="#id27" name="iterator-facade-iterator-category"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></h2>
|
||||
<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade<X,V,R,C,D></span></tt>
|
||||
is a type which satisfies the following conditions:</p>
|
||||
<blockquote>
|
||||
satisfies the following conditions:</p>
|
||||
<ul>
|
||||
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
|
||||
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
|
||||
@ -509,7 +508,9 @@ convertible, and not to any more-derived traversal tag type.</p>
|
||||
</ul>
|
||||
</li>
|
||||
</ul>
|
||||
</blockquote>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
</div>
|
||||
<div class="section" id="iterator-facade-operations">
|
||||
<h2><a class="toc-backref" href="#id28" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h2>
|
||||
@ -1132,7 +1133,6 @@ even be superior.</p>
|
||||
<hr class="footer" />
|
||||
<div class="footer">
|
||||
<a class="reference" href="iterator_facade.rst">View document source</a>.
|
||||
Generated on: 2004-01-13 18:05 UTC.
|
||||
Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
|
||||
</div>
|
||||
</body>
|
||||
|
||||
@ -173,44 +173,9 @@ interoperable with ``X``.
|
||||
-------------------------------------
|
||||
|
||||
The ``iterator_category`` member of ``iterator_facade<X,V,R,C,D>``
|
||||
is a type which satisfies the following conditions:
|
||||
|
||||
* if ``C`` is convertible to ``std::input_iterator_tag`` or
|
||||
``C`` is convertible to ``std::output_iterator_tag``,
|
||||
``iterator_category`` is the same as ``C``.
|
||||
|
||||
* Otherwise, if ``C`` is not convertible to
|
||||
``incrementable_traversal_tag``, the program is ill-formed
|
||||
|
||||
* Otherwise:
|
||||
|
||||
- ``iterator_category`` is convertible to the iterator
|
||||
category tag or tags given by the following algorithm, and
|
||||
not to any more-derived iterator category tag or tags::
|
||||
|
||||
if (R is a reference type
|
||||
&& C is convertible to forward_traversal_tag)
|
||||
{
|
||||
if (C is convertible to random_access_traversal_tag)
|
||||
random_access_iterator_tag
|
||||
else if (C is convertible to bidirectional_traversal_tag)
|
||||
bidirectional_iterator_tag
|
||||
else
|
||||
forward_iterator_tag
|
||||
}
|
||||
else
|
||||
{
|
||||
if (C is convertible to single_pass_traversal_tag
|
||||
&& R is convertible to V)
|
||||
input_iterator_tag
|
||||
else
|
||||
C
|
||||
}
|
||||
|
||||
- ``iterator_traversal<X>::type`` is convertible to the most
|
||||
derived traversal tag type to which ``C`` is also
|
||||
convertible, and not to any more-derived traversal tag type.
|
||||
satisfies the following conditions:
|
||||
|
||||
.. include:: facade_iterator_category.rst
|
||||
|
||||
``iterator_facade`` operations
|
||||
------------------------------
|
||||
|
||||
180
doc/pointee.html
Executable file
180
doc/pointee.html
Executable file
@ -0,0 +1,180 @@
|
||||
<?xml version="1.0" encoding="utf-8" ?>
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||||
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
||||
<meta name="generator" content="Docutils 0.3.1: http://docutils.sourceforge.net/" />
|
||||
<title>pointee and indirect_reference</title>
|
||||
<meta name="author" content="David Abrahams" />
|
||||
<meta name="organization" content="Boost Consulting" />
|
||||
<meta name="date" content="2004-01-13" />
|
||||
<meta name="copyright" content="Copyright David Abrahams 2004. All rights reserved" />
|
||||
<link rel="stylesheet" href="default.css" type="text/css" />
|
||||
</head>
|
||||
<body>
|
||||
<div class="document" id="pointee-and-indirect-reference">
|
||||
<h1 class="title"><tt class="literal"><span class="pre">pointee</span></tt> and <tt class="literal"><span class="pre">indirect_reference</span></tt></h1>
|
||||
<table class="docinfo" frame="void" rules="none">
|
||||
<col class="docinfo-name" />
|
||||
<col class="docinfo-content" />
|
||||
<tbody valign="top">
|
||||
<tr><th class="docinfo-name">Author:</th>
|
||||
<td>David Abrahams</td></tr>
|
||||
<tr><th class="docinfo-name">Contact:</th>
|
||||
<td><a class="first reference" href="mailto:dave@boost-consulting.com">dave@boost-consulting.com</a>, <a class="reference" href="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</a>, <a class="last reference" href="mailto:witt@ive.uni-hannover.de">witt@ive.uni-hannover.de</a></td></tr>
|
||||
<tr><th class="docinfo-name">Organization:</th>
|
||||
<td><a class="first last reference" href="http://www.boost-consulting.com">Boost Consulting</a></td></tr>
|
||||
<tr><th class="docinfo-name">Date:</th>
|
||||
<td>2004-01-13</td></tr>
|
||||
<tr><th class="docinfo-name">Copyright:</th>
|
||||
<td>Copyright David Abrahams 2004. All rights reserved</td></tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">abstract:</th><td class="field-body">Provides the capability to deduce the referent types of
|
||||
pointers, smart pointers and iterators in generic code.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<div class="section" id="overview">
|
||||
<h1><a name="overview">Overview</a></h1>
|
||||
<p>Have you ever wanted to write a generic function that can operate
|
||||
on any kind of dereferenceable object? If you have, you've
|
||||
probably run into the problem of how to determine the type that the
|
||||
object "points at":</p>
|
||||
<pre class="literal-block">
|
||||
template <class Dereferenceable>
|
||||
void f(Dereferenceable p)
|
||||
{
|
||||
<em>what-goes-here?</em> value = *p;
|
||||
...
|
||||
}
|
||||
</pre>
|
||||
<div class="section" id="pointee">
|
||||
<h2><a name="pointee"><tt class="literal"><span class="pre">pointee</span></tt></a></h2>
|
||||
<p>It turns out to be impossible to come up with a fully-general
|
||||
algorithm to do determine <em>what-goes-here</em> directly, but it is
|
||||
possible to require that <tt class="literal"><span class="pre">pointee<Dereferenceable>::type</span></tt> is
|
||||
correct. Naturally, <tt class="literal"><span class="pre">pointee</span></tt> has the same difficulty: it can't
|
||||
determine the appropriate <tt class="literal"><span class="pre">::type</span></tt> reliably for all
|
||||
<tt class="literal"><span class="pre">Dereferenceable</span></tt>s, but it makes very good guesses (it works
|
||||
for all pointers, standard and boost smart pointers, and
|
||||
iterators), and when it guesses wrongly, it can be specialized as
|
||||
neccessary:</p>
|
||||
<pre class="literal-block">
|
||||
namespace boost
|
||||
{
|
||||
template <class T>
|
||||
struct pointee<third_party_lib::smart_pointer<T> >
|
||||
{
|
||||
typedef T type;
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
</div>
|
||||
<div class="section" id="indirect-reference">
|
||||
<h2><a name="indirect-reference"><tt class="literal"><span class="pre">indirect_reference</span></tt></a></h2>
|
||||
<p><tt class="literal"><span class="pre">indirect_reference<T>::type</span></tt> is rather more specialized than
|
||||
<tt class="literal"><span class="pre">pointee</span></tt>, and is meant to be used to forward the result of
|
||||
dereferencing an object of its argument type. Most dereferenceable
|
||||
types just return a reference to their pointee, but some return
|
||||
proxy references or return the pointee by value. When that
|
||||
information is needed, call on <tt class="literal"><span class="pre">indirect_reference</span></tt>.</p>
|
||||
<p>Both of these templates are essential to the correct functioning of
|
||||
<a class="reference" href="indirect_iterator.html"><tt class="literal"><span class="pre">indirect_iterator</span></tt></a>.</p>
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="reference">
|
||||
<h1><a name="reference">Reference</a></h1>
|
||||
<div class="section" id="id1">
|
||||
<h2><a name="id1"><tt class="literal"><span class="pre">pointee</span></tt></a></h2>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
<pre class="literal-block">
|
||||
template <class Dereferenceable>
|
||||
struct pointee
|
||||
{
|
||||
typedef /* see below */ type;
|
||||
};
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Requires:</th><td class="field-body">For an object <tt class="literal"><span class="pre">x</span></tt> of type <tt class="literal"><span class="pre">Dereferenceable</span></tt>, <tt class="literal"><span class="pre">*x</span></tt>
|
||||
is well-formed. If <tt class="literal"><span class="pre">++x</span></tt> is ill-formed it shall neither be
|
||||
ambiguous nor shall it violate access control, and
|
||||
<tt class="literal"><span class="pre">Dereferenceable::element_type</span></tt> shall be an accessible type.
|
||||
Otherwise <tt class="literal"><span class="pre">iterator_traits<Dereferenceable>::value_type</span></tt> shall
|
||||
be well formed. [Note: These requirements need not apply to
|
||||
explicit or partial specializations of <tt class="literal"><span class="pre">pointee</span></tt>]</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<p><tt class="literal"><span class="pre">type</span></tt> is determined according to the following algorithm, where
|
||||
<tt class="literal"><span class="pre">x</span></tt> is an object of type <tt class="literal"><span class="pre">Dereferenceable</span></tt>:</p>
|
||||
<pre class="literal-block">
|
||||
if ( ++x is ill-formed )
|
||||
{
|
||||
return ``Dereferenceable::element_type``
|
||||
}
|
||||
else if (``*x`` is a mutable reference to
|
||||
std::iterator_traits<Dereferenceable>::value_type)
|
||||
{
|
||||
return iterator_traits<Dereferenceable>::value_type
|
||||
}
|
||||
else
|
||||
{
|
||||
return iterator_traits<Dereferenceable>::value_type const
|
||||
}
|
||||
</pre>
|
||||
</div>
|
||||
<div class="section" id="id2">
|
||||
<h2><a name="id2"><tt class="literal"><span class="pre">indirect_reference</span></tt></a></h2>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
<pre class="literal-block">
|
||||
template <class Dereferenceable>
|
||||
struct indirect_reference
|
||||
{
|
||||
typedef /* see below */ type;
|
||||
};
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Requires:</th><td class="field-body">For an object <tt class="literal"><span class="pre">x</span></tt> of type <tt class="literal"><span class="pre">Dereferenceable</span></tt>, <tt class="literal"><span class="pre">*x</span></tt>
|
||||
is well-formed. If <tt class="literal"><span class="pre">++x</span></tt> is ill-formed it shall neither be
|
||||
ambiguous nor shall it violate access control, and
|
||||
<tt class="literal"><span class="pre">pointee<Dereferenceable>::type&</span></tt> shall be well-formed.
|
||||
Otherwise <tt class="literal"><span class="pre">iterator_traits<Dereferenceable>::reference</span></tt> shall
|
||||
be well formed. [Note: These requirements need not apply to
|
||||
explicit or partial specializations of <tt class="literal"><span class="pre">indirect_reference</span></tt>]</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<p><tt class="literal"><span class="pre">type</span></tt> is determined according to the following algorithm, where
|
||||
<tt class="literal"><span class="pre">x</span></tt> is an object of type <tt class="literal"><span class="pre">Dereferenceable</span></tt>:</p>
|
||||
<pre class="literal-block">
|
||||
if ( ++x is ill-formed )
|
||||
return ``pointee<Dereferenceable>::type&``
|
||||
else
|
||||
std::iterator_traits<Dereferenceable>::value_type
|
||||
</pre>
|
||||
</div>
|
||||
</div>
|
||||
</div>
|
||||
<hr class="footer" />
|
||||
<div class="footer">
|
||||
<a class="reference" href="pointee.rst">View document source</a>.
|
||||
Generated on: 2004-01-13.
|
||||
Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
84
doc/pointee.rst
Executable file
84
doc/pointee.rst
Executable file
@ -0,0 +1,84 @@
|
||||
++++++++++++++++++++++++++++++++++++++++
|
||||
``pointee`` and ``indirect_reference``
|
||||
++++++++++++++++++++++++++++++++++++++++
|
||||
|
||||
:Author: David Abrahams
|
||||
:Contact: dave@boost-consulting.com, jsiek@osl.iu.edu, witt@ive.uni-hannover.de
|
||||
:organization: `Boost Consulting`_
|
||||
:date: $Date$
|
||||
:copyright: Copyright David Abrahams 2004. All rights reserved
|
||||
|
||||
.. _`Boost Consulting`: http://www.boost-consulting.com
|
||||
|
||||
:abstract: Provides the capability to deduce the referent types of
|
||||
pointers, smart pointers and iterators in generic code.
|
||||
|
||||
Overview
|
||||
========
|
||||
|
||||
Have you ever wanted to write a generic function that can operate
|
||||
on any kind of dereferenceable object? If you have, you've
|
||||
probably run into the problem of how to determine the type that the
|
||||
object "points at":
|
||||
|
||||
.. parsed-literal::
|
||||
|
||||
template <class Dereferenceable>
|
||||
void f(Dereferenceable p)
|
||||
{
|
||||
*what-goes-here?* value = \*p;
|
||||
...
|
||||
}
|
||||
|
||||
|
||||
``pointee``
|
||||
-----------
|
||||
|
||||
It turns out to be impossible to come up with a fully-general
|
||||
algorithm to do determine *what-goes-here* directly, but it is
|
||||
possible to require that ``pointee<Dereferenceable>::type`` is
|
||||
correct. Naturally, ``pointee`` has the same difficulty: it can't
|
||||
determine the appropriate ``::type`` reliably for all
|
||||
``Dereferenceable``\ s, but it makes very good guesses (it works
|
||||
for all pointers, standard and boost smart pointers, and
|
||||
iterators), and when it guesses wrongly, it can be specialized as
|
||||
neccessary::
|
||||
|
||||
namespace boost
|
||||
{
|
||||
template <class T>
|
||||
struct pointee<third_party_lib::smart_pointer<T> >
|
||||
{
|
||||
typedef T type;
|
||||
};
|
||||
}
|
||||
|
||||
``indirect_reference``
|
||||
----------------------
|
||||
|
||||
``indirect_reference<T>::type`` is rather more specialized than
|
||||
``pointee``, and is meant to be used to forward the result of
|
||||
dereferencing an object of its argument type. Most dereferenceable
|
||||
types just return a reference to their pointee, but some return
|
||||
proxy references or return the pointee by value. When that
|
||||
information is needed, call on ``indirect_reference``.
|
||||
|
||||
Both of these templates are essential to the correct functioning of
|
||||
|indirect_iterator|_.
|
||||
|
||||
.. |indirect_iterator| replace:: ``indirect_iterator``
|
||||
.. _indirect_iterator: indirect_iterator.html
|
||||
|
||||
Reference
|
||||
=========
|
||||
|
||||
``pointee``
|
||||
-----------
|
||||
|
||||
.. include:: pointee_ref.rst
|
||||
|
||||
``indirect_reference``
|
||||
----------------------
|
||||
|
||||
.. include:: indirect_reference_ref.rst
|
||||
|
||||
38
doc/pointee_ref.rst
Executable file
38
doc/pointee_ref.rst
Executable file
@ -0,0 +1,38 @@
|
||||
.. Copyright David Abrahams 2004. Use, modification and distribution is
|
||||
.. subject to the Boost Software License, Version 1.0. (See accompanying
|
||||
.. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
||||
|
||||
::
|
||||
|
||||
template <class Dereferenceable>
|
||||
struct pointee
|
||||
{
|
||||
typedef /* see below */ type;
|
||||
};
|
||||
|
||||
:Requires: For an object ``x`` of type ``Dereferenceable``, ``*x``
|
||||
is well-formed. If ``++x`` is ill-formed it shall neither be
|
||||
ambiguous nor shall it violate access control, and
|
||||
``Dereferenceable::element_type`` shall be an accessible type.
|
||||
Otherwise ``iterator_traits<Dereferenceable>::value_type`` shall
|
||||
be well formed. [Note: These requirements need not apply to
|
||||
explicit or partial specializations of ``pointee``]
|
||||
|
||||
``type`` is determined according to the following algorithm, where
|
||||
``x`` is an object of type ``Dereferenceable``::
|
||||
|
||||
if ( ++x is ill-formed )
|
||||
{
|
||||
return ``Dereferenceable::element_type``
|
||||
}
|
||||
else if (``*x`` is a mutable reference to
|
||||
std::iterator_traits<Dereferenceable>::value_type)
|
||||
{
|
||||
return iterator_traits<Dereferenceable>::value_type
|
||||
}
|
||||
else
|
||||
{
|
||||
return iterator_traits<Dereferenceable>::value_type const
|
||||
}
|
||||
|
||||
|
||||
@ -1,7 +1,7 @@
|
||||
#!/bin/sh
|
||||
PYTHONPATH="c:/src/docutils/docutils;c:/src/docutils/docutils/extras"
|
||||
export PYTHONPATH
|
||||
python c:/src/docutils/docutils/tools/html.py -gdts $1 `echo $1 | sed 's/\(.*\)\..*/\1.html/'`
|
||||
python c:/src/docutils/docutils/tools/html.py -gs $1 `echo $1 | sed 's/\(.*\)\..*/\1.html/'`
|
||||
|
||||
|
||||
|
||||
|
||||
@ -9,6 +9,7 @@ sources = [
|
||||
'function_output_iterator.rst',
|
||||
'index.rst',
|
||||
'indirect_iterator.rst',
|
||||
'pointee.rst',
|
||||
'iterator_adaptor.rst',
|
||||
'iterator_facade.rst',
|
||||
'new-iter-concepts.rst',
|
||||
|
||||
Reference in New Issue
Block a user